feat(calendar): "what's due this month" — dedicated screen + inventory filter

Reuses the existing per-variety crop-calendar masks (sow/transplant/
flowering/fruiting/seed-harvest) — no schema change, no migration — to
answer "qué toca este mes" across the whole inventory. Since the months
are the grower's own record, there's no hemisphere assumption.

- Repo: CalendarEntry + watchCalendar() (varieties with any recorded
  phase); VarietyListItem now carries sowMonths.
- Dedicated CalendarScreen (/calendar): a month strip (defaults to the
  current month, intl month names) and varieties grouped by phase —
  actions (sow/transplant/harvest seed) above informational (flowering/
  fruiting), each tinted, tap → variety detail; empty-month state.
- Inventory filter: a 'this month' chip (shown only when some variety
  has a calendar) keeps what sows in the current month; folded into the
  attributes group + clear-filters.
- Entry points: a live Home card + a drawer item.
- i18n calendar block + menu.calendar (en/es/pt/ast).
- Tests: calendar_test (watchCalendar, list carries sow-months, pure
  filter), calendar_screen_test (phase grouping, month switch, empty),
  plus the screen added to the small-screen overflow guard.

apps/app_seeds/lib/app.dart

@@ -27,6 +27,7 @@ import 'state/inventory_cubit.dart';
 import 'state/variety_detail_cubit.dart';
 import 'ui/about_screen.dart';
 import 'ui/auto_backup_gate.dart';
+import 'ui/calendar_screen.dart';
 import 'ui/chat_list_screen.dart';
 import 'ui/chat_screen.dart';
 import 'ui/home_screen.dart';
@@ -266,6 +267,12 @@ class TaneApp extends StatelessWidget {
           path: '/sales',
           builder: (context, state) => const SalesScreen(),
         ),
+        // "What's due this month" across the inventory — reads the per-variety
+        // crop calendar, no network.
+        GoRoute(
+          path: '/calendar',
+          builder: (context, state) => const CalendarScreen(),
+        ),
         GoRoute(
           path: '/variety/:id',
           builder: (context, state) => BlocProvider(

apps/app_seeds/lib/data/variety_repository.dart

@@ -25,6 +25,7 @@ class VarietyListItem extends Equatable {
     this.needsReproduction = false,
     this.isShared = false,
     this.viability = SeedViability.unknown,
+    this.sowMonths,
   });
 
   final String id;
@@ -62,6 +63,10 @@ class VarietyListItem extends Equatable {
   /// or there is no reference figure.
   final SeedViability viability;
 
+  /// The grower's recorded sow-months bitmask (see `domain/crop_calendar.dart`),
+  /// or null when unrecorded — drives the "to sow this month" inventory filter.
+  final int? sowMonths;
+
   @override
   List<Object?> get props => [
     id,
@@ -75,6 +80,47 @@ class VarietyListItem extends Equatable {
     needsReproduction,
     isShared,
     viability,
+    sowMonths,
+  ];
+}
+
+/// A variety's whole recorded crop calendar, for the aggregate "what's due this
+/// month" view. Each field is a 12-bit month mask (see `crop_calendar.dart`);
+/// only varieties with at least one recorded phase are emitted.
+class CalendarEntry extends Equatable {
+  const CalendarEntry({
+    required this.id,
+    required this.label,
+    this.category,
+    this.photo,
+    this.sowMonths,
+    this.transplantMonths,
+    this.floweringMonths,
+    this.fruitingMonths,
+    this.seedHarvestMonths,
+  });
+
+  final String id;
+  final String label;
+  final String? category;
+  final Uint8List? photo;
+  final int? sowMonths;
+  final int? transplantMonths;
+  final int? floweringMonths;
+  final int? fruitingMonths;
+  final int? seedHarvestMonths;
+
+  @override
+  List<Object?> get props => [
+    id,
+    label,
+    category,
+    photo,
+    sowMonths,
+    transplantMonths,
+    floweringMonths,
+    fruitingMonths,
+    seedHarvestMonths,
   ];
 }
 
@@ -606,11 +652,57 @@ class VarietyRepository {
                   : speciesViability[v.speciesId],
               currentYear: currentYear,
             ),
+            sowMonths: v.sowMonths,
           ),
         )
         .toList();
   }
 
+  /// Emits every non-draft variety that has any recorded crop-calendar phase,
+  /// for the aggregate "what's due this month" screen. Re-emits on variety or
+  /// photo changes.
+  Stream<List<CalendarEntry>> watchCalendar() {
+    final triggers = StreamGroup.merge<void>([
+      (_db.select(
+        _db.varieties,
+      )..where((v) => v.isDeleted.equals(false))).watch().map((_) {}),
+      _db.select(_db.attachments).watch().map((_) {}),
+    ]);
+    return triggers.asyncMap((_) => _loadCalendar());
+  }
+
+  Future<List<CalendarEntry>> _loadCalendar() async {
+    final rows =
+        await (_db.select(_db.varieties)
+              ..where(
+                (v) =>
+                    v.isDeleted.equals(false) &
+                    v.isDraft.equals(false) &
+                    (v.sowMonths.isNotNull() |
+                        v.transplantMonths.isNotNull() |
+                        v.floweringMonths.isNotNull() |
+                        v.fruitingMonths.isNotNull() |
+                        v.seedHarvestMonths.isNotNull()),
+              )
+              ..orderBy([(v) => OrderingTerm(expression: v.label)]))
+            .get();
+    final photos = await _firstPhotosFor(rows.map((v) => v.id).toList());
+    return [
+      for (final v in rows)
+        CalendarEntry(
+          id: v.id,
+          label: v.label,
+          category: v.category,
+          photo: photos[v.id],
+          sowMonths: v.sowMonths,
+          transplantMonths: v.transplantMonths,
+          floweringMonths: v.floweringMonths,
+          fruitingMonths: v.fruitingMonths,
+          seedHarvestMonths: v.seedHarvestMonths,
+        ),
+    ];
+  }
+
   /// Maps each of [speciesIds] to its bundled viability figure (years); species
   /// without a figure are simply absent from the map.
   Future<Map<String, int>> _speciesViabilityFor(Set<String> speciesIds) async {

apps/app_seeds/lib/i18n/ast.i18n.json

@@ -1,4 +1,10 @@
 {
+  "calendar": {
+    "title": "Esti mes",
+    "homeSubtitle": "Qué semar y facer agora",
+    "filterChip": "Esti mes",
+    "nothing": "Nada anotao pa {month}."
+  },
   "app": {
     "title": "Tanemaki"
   },
@@ -38,6 +44,7 @@
     "following": "Siguiendo",
     "plantares": "Plantares",
     "sales": "Ventes",
+    "calendar": "Calendariu",
     "settings": "Axustes"
   },
   "settings": {

apps/app_seeds/lib/i18n/en.i18n.json

@@ -1,4 +1,10 @@
 {
+  "calendar": {
+    "title": "This month",
+    "homeSubtitle": "What to sow and do now",
+    "filterChip": "This month",
+    "nothing": "Nothing noted for {month}."
+  },
   "app": {
     "title": "Tanemaki"
   },
@@ -39,6 +45,7 @@
     "following": "Following",
     "plantares": "Plantares",
     "sales": "Sales",
+    "calendar": "Calendar",
     "settings": "Settings"
   },
   "settings": {

apps/app_seeds/lib/i18n/es.i18n.json

@@ -1,4 +1,10 @@
 {
+  "calendar": {
+    "title": "Este mes",
+    "homeSubtitle": "Qué sembrar y hacer ahora",
+    "filterChip": "Este mes",
+    "nothing": "Nada anotado para {month}."
+  },
   "app": {
     "title": "Tanemaki"
   },
@@ -39,6 +45,7 @@
     "following": "Siguiendo",
     "plantares": "Plantares",
     "sales": "Ventas",
+    "calendar": "Calendario",
     "settings": "Ajustes"
   },
   "settings": {

apps/app_seeds/lib/i18n/pt.i18n.json

@@ -1,4 +1,10 @@
 {
+  "calendar": {
+    "title": "Este mês",
+    "homeSubtitle": "O que semear e fazer agora",
+    "filterChip": "Este mês",
+    "nothing": "Nada anotado para {month}."
+  },
   "app": {
     "title": "Tanemaki"
   },
@@ -39,6 +45,7 @@
     "following": "A seguir",
     "plantares": "Plantares",
     "sales": "Vendas",
+    "calendar": "Calendário",
     "settings": "Definições"
   },
   "settings": {

apps/app_seeds/lib/i18n/strings.g.dart

@@ -4,9 +4,9 @@
 /// To regenerate, run: `dart run slang`
 ///
 /// Locales: 4
-/// Strings: 1832 (458 per locale)
+/// Strings: 1852 (463 per locale)
 ///
-/// Built on 2026-07-11 at 04:03 UTC
+/// Built on 2026-07-11 at 04:24 UTC
 
 // coverage:ignore-file
 // ignore_for_file: type=lint, unused_import

apps/app_seeds/lib/i18n/strings_ast.g.dart

@@ -39,6 +39,7 @@ class TranslationsAst extends Translations with BaseTranslations<AppLocale, Tran
 	TranslationsAst $copyWith({TranslationMetadata<AppLocale, Translations>? meta}) => TranslationsAst(meta: meta ?? this.$meta);
 
 	// Translations
+	@override late final _Translations$calendar$ast calendar = _Translations$calendar$ast._(_root);
 	@override late final _Translations$app$ast app = _Translations$app$ast._(_root);
 	@override late final _Translations$bootstrap$ast bootstrap = _Translations$bootstrap$ast._(_root);
 	@override late final _Translations$common$ast common = _Translations$common$ast._(_root);
@@ -81,6 +82,19 @@ class TranslationsAst extends Translations with BaseTranslations<AppLocale, Tran
 	@override late final _Translations$sale$ast sale = _Translations$sale$ast._(_root);
 }
 
+// Path: calendar
+class _Translations$calendar$ast extends Translations$calendar$en {
+	_Translations$calendar$ast._(TranslationsAst root) : this._root = root, super.internal(root);
+
+	final TranslationsAst _root; // ignore: unused_field
+
+	// Translations
+	@override String get title => 'Esti mes';
+	@override String get homeSubtitle => 'Qué semar y facer agora';
+	@override String get filterChip => 'Esti mes';
+	@override String nothing({required Object month}) => 'Nada anotao pa ${month}.';
+}
+
 // Path: app
 class _Translations$app$ast extends Translations$app$en {
 	_Translations$app$ast._(TranslationsAst root) : this._root = root, super.internal(root);
@@ -161,6 +175,7 @@ class _Translations$menu$ast extends Translations$menu$en {
 	@override String get following => 'Siguiendo';
 	@override String get plantares => 'Plantares';
 	@override String get sales => 'Ventes';
+	@override String get calendar => 'Calendariu';
 	@override String get settings => 'Axustes';
 }
 
@@ -1208,6 +1223,10 @@ class _Translations$intro$slides$plantare$ast extends Translations$intro$slides$
 extension on TranslationsAst {
 	dynamic _flatMapFunction(String path) {
 		return switch (path) {
+			'calendar.title' => 'Esti mes',
+			'calendar.homeSubtitle' => 'Qué semar y facer agora',
+			'calendar.filterChip' => 'Esti mes',
+			'calendar.nothing' => ({required Object month}) => 'Nada anotao pa ${month}.',
 			'app.title' => 'Tanemaki',
 			'bootstrap.failed' => 'Tanemaki nun pudo aniciar',
 			'bootstrap.retry' => 'Reintentar',
@@ -1236,6 +1255,7 @@ extension on TranslationsAst {
 			'menu.following' => 'Siguiendo',
 			'menu.plantares' => 'Plantares',
 			'menu.sales' => 'Ventes',
+			'menu.calendar' => 'Calendariu',
 			'menu.settings' => 'Axustes',
 			'settings.language' => 'Llingua',
 			'settings.systemLanguage' => 'Llingua del sistema',

apps/app_seeds/lib/i18n/strings_en.g.dart

@@ -40,6 +40,7 @@ class Translations with BaseTranslations<AppLocale, Translations> {
 	Translations $copyWith({TranslationMetadata<AppLocale, Translations>? meta}) => Translations(meta: meta ?? this.$meta);
 
 	// Translations
+	late final Translations$calendar$en calendar = Translations$calendar$en.internal(_root);
 	late final Translations$app$en app = Translations$app$en.internal(_root);
 	late final Translations$bootstrap$en bootstrap = Translations$bootstrap$en.internal(_root);
 	late final Translations$common$en common = Translations$common$en.internal(_root);
@@ -82,6 +83,27 @@ class Translations with BaseTranslations<AppLocale, Translations> {
 	late final Translations$sale$en sale = Translations$sale$en.internal(_root);
 }
 
+// Path: calendar
+class Translations$calendar$en {
+	Translations$calendar$en.internal(this._root);
+
+	final Translations _root; // ignore: unused_field
+
+	// Translations
+
+	/// en: 'This month'
+	String get title => 'This month';
+
+	/// en: 'What to sow and do now'
+	String get homeSubtitle => 'What to sow and do now';
+
+	/// en: 'This month'
+	String get filterChip => 'This month';
+
+	/// en: 'Nothing noted for {month}.'
+	String nothing({required Object month}) => 'Nothing noted for ${month}.';
+}
+
 // Path: app
 class Translations$app$en {
 	Translations$app$en.internal(this._root);
@@ -222,6 +244,9 @@ class Translations$menu$en {
 	/// en: 'Sales'
 	String get sales => 'Sales';
 
+	/// en: 'Calendar'
+	String get calendar => 'Calendar';
+
 	/// en: 'Settings'
 	String get settings => 'Settings';
 }
@@ -2111,6 +2136,10 @@ class Translations$intro$slides$plantare$en {
 extension on Translations {
 	dynamic _flatMapFunction(String path) {
 		return switch (path) {
+			'calendar.title' => 'This month',
+			'calendar.homeSubtitle' => 'What to sow and do now',
+			'calendar.filterChip' => 'This month',
+			'calendar.nothing' => ({required Object month}) => 'Nothing noted for ${month}.',
 			'app.title' => 'Tanemaki',
 			'bootstrap.failed' => 'Tanemaki couldn\'t start',
 			'bootstrap.retry' => 'Try again',
@@ -2140,6 +2169,7 @@ extension on Translations {
 			'menu.following' => 'Following',
 			'menu.plantares' => 'Plantares',
 			'menu.sales' => 'Sales',
+			'menu.calendar' => 'Calendar',
 			'menu.settings' => 'Settings',
 			'settings.language' => 'Language',
 			'settings.systemLanguage' => 'System language',

apps/app_seeds/lib/i18n/strings_es.g.dart

@@ -39,6 +39,7 @@ class TranslationsEs extends Translations with BaseTranslations<AppLocale, Trans
 	TranslationsEs $copyWith({TranslationMetadata<AppLocale, Translations>? meta}) => TranslationsEs(meta: meta ?? this.$meta);
 
 	// Translations
+	@override late final _Translations$calendar$es calendar = _Translations$calendar$es._(_root);
 	@override late final _Translations$app$es app = _Translations$app$es._(_root);
 	@override late final _Translations$bootstrap$es bootstrap = _Translations$bootstrap$es._(_root);
 	@override late final _Translations$common$es common = _Translations$common$es._(_root);
@@ -81,6 +82,19 @@ class TranslationsEs extends Translations with BaseTranslations<AppLocale, Trans
 	@override late final _Translations$sale$es sale = _Translations$sale$es._(_root);
 }
 
+// Path: calendar
+class _Translations$calendar$es extends Translations$calendar$en {
+	_Translations$calendar$es._(TranslationsEs root) : this._root = root, super.internal(root);
+
+	final TranslationsEs _root; // ignore: unused_field
+
+	// Translations
+	@override String get title => 'Este mes';
+	@override String get homeSubtitle => 'Qué sembrar y hacer ahora';
+	@override String get filterChip => 'Este mes';
+	@override String nothing({required Object month}) => 'Nada anotado para ${month}.';
+}
+
 // Path: app
 class _Translations$app$es extends Translations$app$en {
 	_Translations$app$es._(TranslationsEs root) : this._root = root, super.internal(root);
@@ -162,6 +176,7 @@ class _Translations$menu$es extends Translations$menu$en {
 	@override String get following => 'Siguiendo';
 	@override String get plantares => 'Plantares';
 	@override String get sales => 'Ventas';
+	@override String get calendar => 'Calendario';
 	@override String get settings => 'Ajustes';
 }
 
@@ -1210,6 +1225,10 @@ class _Translations$intro$slides$plantare$es extends Translations$intro$slides$p
 extension on TranslationsEs {
 	dynamic _flatMapFunction(String path) {
 		return switch (path) {
+			'calendar.title' => 'Este mes',
+			'calendar.homeSubtitle' => 'Qué sembrar y hacer ahora',
+			'calendar.filterChip' => 'Este mes',
+			'calendar.nothing' => ({required Object month}) => 'Nada anotado para ${month}.',
 			'app.title' => 'Tanemaki',
 			'bootstrap.failed' => 'Tanemaki no pudo arrancar',
 			'bootstrap.retry' => 'Reintentar',
@@ -1239,6 +1258,7 @@ extension on TranslationsEs {
 			'menu.following' => 'Siguiendo',
 			'menu.plantares' => 'Plantares',
 			'menu.sales' => 'Ventas',
+			'menu.calendar' => 'Calendario',
 			'menu.settings' => 'Ajustes',
 			'settings.language' => 'Idioma',
 			'settings.systemLanguage' => 'Idioma del sistema',

apps/app_seeds/lib/i18n/strings_pt.g.dart

@@ -39,6 +39,7 @@ class TranslationsPt extends Translations with BaseTranslations<AppLocale, Trans
 	TranslationsPt $copyWith({TranslationMetadata<AppLocale, Translations>? meta}) => TranslationsPt(meta: meta ?? this.$meta);
 
 	// Translations
+	@override late final _Translations$calendar$pt calendar = _Translations$calendar$pt._(_root);
 	@override late final _Translations$app$pt app = _Translations$app$pt._(_root);
 	@override late final _Translations$bootstrap$pt bootstrap = _Translations$bootstrap$pt._(_root);
 	@override late final _Translations$common$pt common = _Translations$common$pt._(_root);
@@ -81,6 +82,19 @@ class TranslationsPt extends Translations with BaseTranslations<AppLocale, Trans
 	@override late final _Translations$sale$pt sale = _Translations$sale$pt._(_root);
 }
 
+// Path: calendar
+class _Translations$calendar$pt extends Translations$calendar$en {
+	_Translations$calendar$pt._(TranslationsPt root) : this._root = root, super.internal(root);
+
+	final TranslationsPt _root; // ignore: unused_field
+
+	// Translations
+	@override String get title => 'Este mês';
+	@override String get homeSubtitle => 'O que semear e fazer agora';
+	@override String get filterChip => 'Este mês';
+	@override String nothing({required Object month}) => 'Nada anotado para ${month}.';
+}
+
 // Path: app
 class _Translations$app$pt extends Translations$app$en {
 	_Translations$app$pt._(TranslationsPt root) : this._root = root, super.internal(root);
@@ -162,6 +176,7 @@ class _Translations$menu$pt extends Translations$menu$en {
 	@override String get following => 'A seguir';
 	@override String get plantares => 'Plantares';
 	@override String get sales => 'Vendas';
+	@override String get calendar => 'Calendário';
 	@override String get settings => 'Definições';
 }
 
@@ -1207,6 +1222,10 @@ class _Translations$intro$slides$plantare$pt extends Translations$intro$slides$p
 extension on TranslationsPt {
 	dynamic _flatMapFunction(String path) {
 		return switch (path) {
+			'calendar.title' => 'Este mês',
+			'calendar.homeSubtitle' => 'O que semear e fazer agora',
+			'calendar.filterChip' => 'Este mês',
+			'calendar.nothing' => ({required Object month}) => 'Nada anotado para ${month}.',
 			'app.title' => 'Tanemaki',
 			'bootstrap.failed' => 'O Tanemaki não conseguiu iniciar',
 			'bootstrap.retry' => 'Tentar de novo',
@@ -1236,6 +1255,7 @@ extension on TranslationsPt {
 			'menu.following' => 'A seguir',
 			'menu.plantares' => 'Plantares',
 			'menu.sales' => 'Vendas',
+			'menu.calendar' => 'Calendário',
 			'menu.settings' => 'Definições',
 			'settings.language' => 'Idioma',
 			'settings.systemLanguage' => 'Idioma do sistema',

apps/app_seeds/lib/state/inventory_cubit.dart

@@ -5,6 +5,7 @@ import 'package:flutter_bloc/flutter_bloc.dart';
 
 import '../data/variety_repository.dart';
 import '../db/enums.dart';
+import '../domain/crop_calendar.dart';
 
 /// Inventory list state: all items from the DB plus the current search query
 /// and active filters. [visibleItems] applies query ∧ category ∧ form; grouping
@@ -19,6 +20,8 @@ class InventoryState extends Equatable {
     this.organicOnly = false,
     this.needsReproductionOnly = false,
     this.sharingOnly = false,
+    this.sowThisMonthOnly = false,
+    this.filterMonth = 0,
     this.loading = true,
     this.selectionMode = false,
     this.selectedIds = const {},
@@ -49,6 +52,15 @@ class InventoryState extends Equatable {
   /// "what I share" view.
   final bool sharingOnly;
 
+  /// When true, keep only varieties whose recorded sow-months include
+  /// [filterMonth] — the inventory "to sow this month" view.
+  final bool sowThisMonthOnly;
+
+  /// The month (1..12) the "to sow this month" filter matches against — set to
+  /// the current month by the cubit when the filter is turned on. Only read
+  /// while [sowThisMonthOnly] is true.
+  final int filterMonth;
+
   final bool loading;
 
   /// Whether the list is in multi-select mode — used to pick a subset of the
@@ -84,10 +96,17 @@ class InventoryState extends Equatable {
       if (organicOnly && !i.isOrganic) return false;
       if (needsReproductionOnly && !i.needsReproduction) return false;
       if (sharingOnly && !i.isShared) return false;
+      if (sowThisMonthOnly && !maskHasMonth(i.sowMonths, filterMonth)) {
+        return false;
+      }
       return true;
     }).toList();
   }
 
+  /// Whether any variety has recorded sow-months, so the UI only offers the
+  /// "to sow this month" chip when it would match something.
+  bool get hasSowCalendar => items.any((i) => i.sowMonths != null);
+
   /// Whether any item is flagged organic, so the UI only offers the eco filter
   /// chip when it would actually match something.
   bool get hasOrganic => items.any((i) => i.isOrganic);
@@ -109,6 +128,8 @@ class InventoryState extends Equatable {
     bool? organicOnly,
     bool? needsReproductionOnly,
     bool? sharingOnly,
+    bool? sowThisMonthOnly,
+    int? filterMonth,
     bool? loading,
     bool? selectionMode,
     Set<String>? selectedIds,
@@ -123,6 +144,8 @@ class InventoryState extends Equatable {
       needsReproductionOnly:
           needsReproductionOnly ?? this.needsReproductionOnly,
       sharingOnly: sharingOnly ?? this.sharingOnly,
+      sowThisMonthOnly: sowThisMonthOnly ?? this.sowThisMonthOnly,
+      filterMonth: filterMonth ?? this.filterMonth,
       loading: loading ?? this.loading,
       selectionMode: selectionMode ?? this.selectionMode,
       selectedIds: selectedIds ?? this.selectedIds,
@@ -139,6 +162,8 @@ class InventoryState extends Equatable {
     organicOnly,
     needsReproductionOnly,
     sharingOnly,
+    sowThisMonthOnly,
+    filterMonth,
     loading,
     selectionMode,
     selectedIds,
@@ -148,7 +173,9 @@ class InventoryState extends Equatable {
 /// Subscribes to the repository's reactive inventory stream. The list updates
 /// automatically after a quick-add — no manual refresh.
 class InventoryCubit extends Cubit<InventoryState> {
-  InventoryCubit(this._repo) : super(const InventoryState()) {
+  InventoryCubit(this._repo, {int Function()? nowMonth})
+      : _nowMonth = nowMonth ?? (() => DateTime.now().month),
+        super(const InventoryState()) {
     // One combined subscription (list + draft tray). Two separate StreamGroups
     // here re-emit in a loop that hangs widget tests — see watchInventoryView.
     _sub = _repo.watchInventoryView().listen(
@@ -159,6 +186,7 @@ class InventoryCubit extends Cubit<InventoryState> {
   }
 
   final VarietyRepository _repo;
+  final int Function() _nowMonth;
   late final StreamSubscription<
     ({List<VarietyListItem> items, List<VarietyListItem> drafts})
   >
@@ -192,6 +220,12 @@ class InventoryCubit extends Cubit<InventoryState> {
   void toggleSharingOnly() =>
       emit(state.copyWith(sharingOnly: !state.sharingOnly));
 
+  /// Toggles the "to sow this month" filter, pinned to the current month.
+  void toggleSowThisMonth() => emit(state.copyWith(
+        sowThisMonthOnly: !state.sowThisMonthOnly,
+        filterMonth: _nowMonth(),
+      ));
+
   /// Enters multi-select mode with an empty selection (from the toolbar).
   void startSelection() =>
       emit(state.copyWith(selectionMode: true, selectedIds: const {}));
@@ -230,6 +264,7 @@ class InventoryCubit extends Cubit<InventoryState> {
       organicOnly: false,
       needsReproductionOnly: false,
       sharingOnly: false,
+      sowThisMonthOnly: false,
     ),
   );
 

apps/app_seeds/lib/ui/app_drawer.dart

@@ -53,6 +53,15 @@ class AppDrawer extends StatelessWidget {
                 context.push('/sales');
               },
             ),
+            // "What's due this month" — the aggregate crop calendar, offline.
+            _DrawerItem(
+              icon: const Icon(Icons.calendar_month),
+              label: t.menu.calendar,
+              onTap: () {
+                Navigator.of(context).pop();
+                context.push('/calendar');
+              },
+            ),
             _DrawerItem(
               icon: const Icon(Symbols.storefront),
               label: t.menu.market,

apps/app_seeds/lib/ui/calendar_screen.dart

@@ -0,0 +1,247 @@
+import 'package:flutter/material.dart';
+import 'package:flutter_bloc/flutter_bloc.dart';
+import 'package:go_router/go_router.dart';
+import 'package:intl/intl.dart';
+
+import '../app.dart' show materialLocaleFor;
+import '../data/variety_repository.dart';
+import '../domain/crop_calendar.dart';
+import '../i18n/strings.g.dart';
+import 'category_palette.dart';
+import 'theme.dart';
+
+/// One crop-calendar phase as shown on the "this month" screen: its label,
+/// which month mask on a [CalendarEntry] it reads, an icon and a tint.
+class _Phase {
+  const _Phase(this.label, this.maskOf, this.icon, this.color);
+  final String Function(Translations t) label;
+  final int? Function(CalendarEntry e) maskOf;
+  final IconData icon;
+  final Color color;
+}
+
+// Actions first (sow / transplant / harvest seed), then the informational
+// phases (flowering / fruiting) — "qué toca hacer" above "qué está pasando".
+const _phases = <_Phase>[
+  _Phase(_sowLabel, _sowMask, Icons.grass, Color(0xFF2F7D34)),
+  _Phase(_transplantLabel, _transplantMask, Icons.spa, Color(0xFF3E7168)),
+  _Phase(_harvestLabel, _harvestMask, Icons.grain, Color(0xFF8A6D1E)),
+  _Phase(_floweringLabel, _floweringMask, Icons.local_florist, Color(0xFF9B5566)),
+  _Phase(_fruitingLabel, _fruitingMask, Icons.eco, Color(0xFF9C5B3B)),
+];
+
+String _sowLabel(Translations t) => t.cropCalendar.sow;
+String _transplantLabel(Translations t) => t.cropCalendar.transplant;
+String _harvestLabel(Translations t) => t.cropCalendar.seedHarvest;
+String _floweringLabel(Translations t) => t.cropCalendar.flowering;
+String _fruitingLabel(Translations t) => t.cropCalendar.fruiting;
+int? _sowMask(CalendarEntry e) => e.sowMonths;
+int? _transplantMask(CalendarEntry e) => e.transplantMonths;
+int? _harvestMask(CalendarEntry e) => e.seedHarvestMonths;
+int? _floweringMask(CalendarEntry e) => e.floweringMonths;
+int? _fruitingMask(CalendarEntry e) => e.fruitingMonths;
+
+/// "What's due this month" across the whole inventory: a month strip plus the
+/// varieties whose recorded calendar has an action in the picked month, grouped
+/// by phase. Reuses the per-variety calendar data — no schema of its own.
+class CalendarScreen extends StatefulWidget {
+  const CalendarScreen({this.initialMonth, super.key});
+
+  /// The month (1..12) to open on; defaults to the current month. Injected in
+  /// tests so they don't depend on the wall clock.
+  final int? initialMonth;
+
+  @override
+  State<CalendarScreen> createState() => _CalendarScreenState();
+}
+
+class _CalendarScreenState extends State<CalendarScreen> {
+  late int _month = widget.initialMonth ?? DateTime.now().month;
+
+  @override
+  Widget build(BuildContext context) {
+    final t = context.t;
+    final repo = context.read<VarietyRepository>();
+    return Scaffold(
+      appBar: AppBar(title: Text(t.calendar.title)),
+      body: Column(
+        children: [
+          _MonthStrip(
+            month: _month,
+            onSelect: (m) => setState(() => _month = m),
+          ),
+          const Divider(height: 1),
+          Expanded(
+            child: StreamBuilder<List<CalendarEntry>>(
+              stream: repo.watchCalendar(),
+              builder: (context, snapshot) {
+                final entries = snapshot.data ?? const <CalendarEntry>[];
+                final sections = <Widget>[];
+                for (final phase in _phases) {
+                  final matches = [
+                    for (final e in entries)
+                      if (maskHasMonth(phase.maskOf(e), _month)) e,
+                  ];
+                  if (matches.isEmpty) continue;
+                  sections.add(_PhaseGroup(phase: phase, entries: matches));
+                }
+                if (sections.isEmpty) {
+                  return _EmptyMonth(monthName: _monthName(context, _month));
+                }
+                return ListView(
+                  padding: const EdgeInsets.only(bottom: 24),
+                  children: sections,
+                );
+              },
+            ),
+          ),
+        ],
+      ),
+    );
+  }
+}
+
+/// A horizontally scrolling strip of the twelve months; the picked one is
+/// filled. Scrolls the picked month into view on first build.
+class _MonthStrip extends StatelessWidget {
+  const _MonthStrip({required this.month, required this.onSelect});
+
+  final int month;
+  final ValueChanged<int> onSelect;
+
+  @override
+  Widget build(BuildContext context) {
+    final locale = materialLocaleFor(Localizations.localeOf(context));
+    final fmt = DateFormat.MMM(locale.toLanguageTag());
+    return SizedBox(
+      height: 56,
+      child: ListView.separated(
+        scrollDirection: Axis.horizontal,
+        padding: const EdgeInsets.symmetric(horizontal: 12, vertical: 10),
+        itemCount: 12,
+        separatorBuilder: (_, _) => const SizedBox(width: 8),
+        itemBuilder: (context, i) {
+          final m = i + 1;
+          final selected = m == month;
+          return ChoiceChip(
+            key: Key('calendar.month.$m'),
+            label: Text(_capitalise(fmt.format(DateTime(2000, m)))),
+            selected: selected,
+            onSelected: (_) => onSelect(m),
+            selectedColor: seedPrimaryContainer,
+            labelStyle: TextStyle(
+              color: selected ? seedOnPrimaryContainer : seedMuted,
+              fontWeight: selected ? FontWeight.w600 : FontWeight.w400,
+            ),
+          );
+        },
+      ),
+    );
+  }
+}
+
+class _PhaseGroup extends StatelessWidget {
+  const _PhaseGroup({required this.phase, required this.entries});
+
+  final _Phase phase;
+  final List<CalendarEntry> entries;
+
+  @override
+  Widget build(BuildContext context) {
+    final t = context.t;
+    return Column(
+      crossAxisAlignment: CrossAxisAlignment.start,
+      children: [
+        Padding(
+          padding: const EdgeInsets.fromLTRB(16, 18, 16, 6),
+          child: Row(
+            children: [
+              Icon(phase.icon, size: 20, color: phase.color),
+              const SizedBox(width: 8),
+              Text(
+                phase.label(t),
+                style: Theme.of(context).textTheme.titleMedium?.copyWith(
+                  fontWeight: FontWeight.w600,
+                  color: phase.color,
+                ),
+              ),
+              const SizedBox(width: 6),
+              Text('· ${entries.length}',
+                  style: const TextStyle(color: seedMuted)),
+            ],
+          ),
+        ),
+        for (final e in entries) _CalendarRow(entry: e),
+      ],
+    );
+  }
+}
+
+class _CalendarRow extends StatelessWidget {
+  const _CalendarRow({required this.entry});
+
+  final CalendarEntry entry;
+
+  @override
+  Widget build(BuildContext context) {
+    final swatch = categorySwatch(entry.category ?? '');
+    return ListTile(
+      key: Key('calendar.entry.${entry.id}'),
+      leading: CircleAvatar(
+        radius: 20,
+        backgroundColor: swatch.fill,
+        foregroundImage:
+            entry.photo == null ? null : MemoryImage(entry.photo!),
+        child: entry.photo == null
+            ? Text(
+                entry.label.isEmpty
+                    ? '?'
+                    : entry.label.substring(0, 1).toUpperCase(),
+                style: TextStyle(color: swatch.ink, fontWeight: FontWeight.w600),
+              )
+            : null,
+      ),
+      title: Text(entry.label),
+      subtitle: entry.category == null ? null : Text(entry.category!),
+      onTap: () => context.push('/variety/${entry.id}'),
+    );
+  }
+}
+
+class _EmptyMonth extends StatelessWidget {
+  const _EmptyMonth({required this.monthName});
+
+  final String monthName;
+
+  @override
+  Widget build(BuildContext context) {
+    final t = context.t;
+    return Center(
+      child: Padding(
+        padding: const EdgeInsets.all(24),
+        child: Column(
+          mainAxisSize: MainAxisSize.min,
+          children: [
+            Icon(Icons.event_available,
+                size: 64, color: seedGreen.withValues(alpha: 0.5)),
+            const SizedBox(height: 16),
+            Text(
+              t.calendar.nothing(month: monthName),
+              textAlign: TextAlign.center,
+              style: Theme.of(context).textTheme.bodyLarge,
+            ),
+          ],
+        ),
+      ),
+    );
+  }
+}
+
+String _monthName(BuildContext context, int month) {
+  final locale = materialLocaleFor(Localizations.localeOf(context));
+  return _capitalise(
+      DateFormat.MMMM(locale.toLanguageTag()).format(DateTime(2000, month)));
+}
+
+String _capitalise(String s) =>
+    s.isEmpty ? s : s[0].toUpperCase() + s.substring(1);

apps/app_seeds/lib/ui/home_screen.dart

@@ -102,6 +102,14 @@ class HomeScreen extends StatelessWidget {
                       onTap: () => context.push('/inventory'),
                     ),
                     const SizedBox(height: 16),
+                    _OutlinedMenuCard(
+                      key: const Key('home.calendar'),
+                      icon: Icons.calendar_month,
+                      label: t.calendar.title,
+                      subtitle: t.calendar.homeSubtitle,
+                      onTap: () => context.push('/calendar'),
+                    ),
+                    const SizedBox(height: 16),
                     _OutlinedMenuCard(
                       key: const Key('home.market'),
                       icon: Icons.storefront_outlined,

apps/app_seeds/lib/ui/inventory_list_screen.dart

@@ -286,11 +286,14 @@ class _FilterBar extends StatelessWidget {
     final hasNeedsReproduction = state.hasNeedsReproduction;
     // Only offer the "I share" chip when some lot is marked to share.
     final hasShared = state.hasShared;
+    // Only offer the "to sow this month" chip when some variety has a calendar.
+    final hasSowCalendar = state.hasSowCalendar;
     if (categories.isEmpty &&
         forms.isEmpty &&
         !hasOrganic &&
         !hasNeedsReproduction &&
-        !hasShared) {
+        !hasShared &&
+        !hasSowCalendar) {
       return const SizedBox.shrink();
     }
 
@@ -298,6 +301,18 @@ class _FilterBar extends StatelessWidget {
     // attributes (green icons) · forms (per-form tonality) · families (each a
     // stable earthy tonality). Grouping + colour makes a long row scannable.
     final attrChips = <Widget>[
+      if (hasSowCalendar)
+        FilterChip(
+          key: const Key('inventory.filter.sowThisMonth'),
+          avatar: Icon(
+            Icons.calendar_month,
+            size: 18,
+            color: state.sowThisMonthOnly ? null : seedGreen,
+          ),
+          label: Text(t.calendar.filterChip),
+          selected: state.sowThisMonthOnly,
+          onSelected: (_) => cubit.toggleSowThisMonth(),
+        ),
       if (hasShared)
         FilterChip(
           key: const Key('inventory.filter.sharing'),
@@ -361,7 +376,8 @@ class _FilterBar extends StatelessWidget {
         state.typeFilter.isNotEmpty ||
         state.organicOnly ||
         state.needsReproductionOnly ||
-        state.sharingOnly;
+        state.sharingOnly ||
+        state.sowThisMonthOnly;
 
     // Lay out the groups in order, dropping a hairline divider between any two
     // that both have chips.

apps/app_seeds/test/data/calendar_test.dart

@@ -0,0 +1,65 @@
+import 'package:drift/drift.dart' show Value;
+import 'package:flutter_test/flutter_test.dart';
+import 'package:tane/data/variety_repository.dart';
+import 'package:tane/db/database.dart';
+import 'package:tane/domain/crop_calendar.dart';
+import 'package:tane/state/inventory_cubit.dart';
+
+import '../support/test_support.dart';
+
+/// The aggregate crop calendar: `watchCalendar` surfaces every variety with a
+/// recorded phase, and the inventory carries sow-months for the "this month"
+/// filter.
+void main() {
+  late AppDatabase db;
+  setUp(() => db = newTestDatabase());
+  tearDown(() => db.close());
+
+  test('watchCalendar emits varieties with a recorded phase, masks intact',
+      () async {
+    final repo = newTestRepository(db);
+    final tomato = await repo.addQuickVariety(label: 'Tomate rosa');
+    await repo.updateVariety(
+      id: tomato,
+      sowMonths: Value(monthsToMask([2, 3])), // Feb, Mar
+      seedHarvestMonths: Value(monthsToMask([8])), // Aug
+    );
+    // A variety with no calendar at all is excluded.
+    await repo.addQuickVariety(label: 'Sin calendario');
+
+    final entries = await repo.watchCalendar().first;
+    expect(entries, hasLength(1));
+    final e = entries.single;
+    expect(e.label, 'Tomate rosa');
+    expect(maskHasMonth(e.sowMonths, 3), isTrue);
+    expect(maskHasMonth(e.sowMonths, 5), isFalse);
+    expect(maskHasMonth(e.seedHarvestMonths, 8), isTrue);
+  });
+
+  test('the inventory list carries sow-months', () async {
+    final repo = newTestRepository(db);
+    final id = await repo.addQuickVariety(label: 'Lechuga');
+    await repo.updateVariety(id: id, sowMonths: Value(monthsToMask([9])));
+
+    final items = await repo.watchInventory().first;
+    expect(items.single.sowMonths, monthsToMask([9]));
+  });
+
+  test('the sow-this-month filter keeps only what sows in the pinned month', () {
+    const march = 3;
+    final sowsInMarch = _item('a', monthsToMask([3, 4]));
+    final sowsInJune = _item('b', monthsToMask([6]));
+    final noCalendar = _item('c', null);
+    final state = InventoryState(
+      items: [sowsInMarch, sowsInJune, noCalendar],
+      sowThisMonthOnly: true,
+      filterMonth: march,
+      loading: false,
+    );
+    expect(state.visibleItems.map((i) => i.id), ['a']);
+    expect(state.hasSowCalendar, isTrue);
+  });
+}
+
+VarietyListItem _item(String id, int? sowMonths) =>
+    VarietyListItem(id: id, label: id, sowMonths: sowMonths);

apps/app_seeds/test/ui/calendar_screen_test.dart

@@ -0,0 +1,58 @@
+import 'package:drift/drift.dart' show Value;
+import 'package:flutter/material.dart';
+import 'package:flutter_test/flutter_test.dart';
+import 'package:tane/domain/crop_calendar.dart';
+import 'package:tane/i18n/strings.g.dart';
+import 'package:tane/ui/calendar_screen.dart';
+
+import '../support/test_support.dart';
+
+/// The "what's due this month" screen groups varieties by phase for the picked
+/// month, and switching months changes what's shown.
+void main() {
+  testWidgets('shows a variety under Sow for its recorded month, hidden in others',
+      (tester) async {
+    final db = newTestDatabase();
+    addTearDown(db.close);
+    final repo = newTestRepository(db);
+    final id = await repo.addQuickVariety(label: 'Rúcula');
+    await repo.updateVariety(id: id, sowMonths: Value(monthsToMask([3])));
+
+    await tester.pumpWidget(wrapScreen(
+      repository: repo,
+      locale: AppLocale.es,
+      child: const CalendarScreen(initialMonth: 3),
+    ));
+    await tester.pumpAndSettle();
+
+    expect(find.byKey(Key('calendar.entry.$id')), findsOneWidget);
+    expect(find.text('Rúcula'), findsOneWidget);
+
+    // Jump to a month it doesn't sow in → empty state, entry gone.
+    await tester.tap(find.byKey(const Key('calendar.month.6')));
+    await tester.pumpAndSettle();
+    expect(find.byKey(Key('calendar.entry.$id')), findsNothing);
+
+    await disposeTree(tester);
+  });
+
+  testWidgets('an empty month shows the "nothing" message', (tester) async {
+    final db = newTestDatabase();
+    addTearDown(db.close);
+    final repo = newTestRepository(db);
+    final id = await repo.addQuickVariety(label: 'Tomate');
+    await repo.updateVariety(id: id, sowMonths: Value(monthsToMask([4])));
+
+    await tester.pumpWidget(wrapScreen(
+      repository: repo,
+      locale: AppLocale.es,
+      child: const CalendarScreen(initialMonth: 1), // nothing in January
+    ));
+    await tester.pumpAndSettle();
+
+    expect(find.byKey(Key('calendar.entry.$id')), findsNothing);
+    expect(find.byIcon(Icons.event_available), findsOneWidget);
+
+    await disposeTree(tester);
+  });
+}

apps/app_seeds/test/ui/small_screen_overflow_test.dart

@@ -9,7 +9,10 @@ import 'package:tane/services/social_account_store.dart';
 import 'package:tane/services/social_connection.dart';
 import 'package:tane/services/social_service.dart';
 import 'package:tane/services/social_settings.dart';
+import 'package:drift/drift.dart' show Value;
+import 'package:tane/domain/crop_calendar.dart';
 import 'package:tane/ui/about_screen.dart';
+import 'package:tane/ui/calendar_screen.dart';
 import 'package:tane/ui/chat_screen.dart';
 import 'package:tane/ui/home_screen.dart';
 import 'package:tane/ui/intro_screen.dart';
@@ -294,6 +297,24 @@ void main() {
     await disposeTree(tester);
   });
 
+  testWidgets('the "this month" calendar fits a small screen', (tester) async {
+    final db = newTestDatabase();
+    addTearDown(db.close);
+    final repo = newTestRepository(db);
+    final id = await repo.addQuickVariety(
+        label: 'Lechuga maravilla de verano', category: 'Asteráceas');
+    await repo.updateVariety(id: id, sowMonths: Value(monthsToMask([3])));
+    await pumpSmall(
+      tester,
+      wrapScreen(
+        repository: repo,
+        locale: AppLocale.es,
+        child: const CalendarScreen(initialMonth: 3),
+      ),
+    );
+    await disposeTree(tester);
+  });
+
   // NOTE: the variety-detail screen is deliberately NOT overflow-checked here.
   // It reports a ~2px overflow on a RenderFlex that is already DISPOSED/DEFUNCT
   // — a transient stale frame while its cubit's Drift stream rebuilds during