The blackberry is popular for making jams, wine, and dessert filling.
In general, berries should be dry, firm, well-shaped, and eaten within a week after purchase. If you can’t eat them that soon, remember that berries freeze well! It’s best to buy berries that are ‘in-season’ as they’ll cost less and are more ripe and flavorful than ‘out-of-season’ berries.
Stay away from containers of berries with juice stains which may be a sign that the berries are crushed and possibly moldy; soft, watery fruit that means the berries are overripe; dehydrated, wrinkled fruit that means the berries have been stored too long.
Select blackberries that are unblemished and dry, in an unstained container. Blackberries should be shiny and black — avoid those that are dull or reddish. Moisture will increase spoilage, so the berries themselves should be relatively dry. Shelf life for blackberries is short, so they should be consumed within 2–3 days of purchase. Eat at room temperature for fullest flavor.
A 16 oz. bag of whole frozen blackberries is equal to about 3 cups frozen berries.
Store whole frozen berries in their unopened or tightly resealed packages in your freezer. If berries are to be served alone, thaw until they are pliable and serve partially frozen. Add sugar to taste — it brings out both the flavor and the luscious juices.
Since blackberry plants easily hybridize, there are many cultivars with more than one species in their ancestry.
- Dewberries (R. caesius) are smaller than blackberries and can be distinguished by the white waxy coating on the fruits, which also usually have fewer drupelets.
- Boysenberries were bred from blackberries, loganberries, and raspberries.
|Seasonality tables|Autumn|Winter|Spring|Summer|All year|
Blackberries reach their peak towards the end of summer, specifically July to August. In warmer climates, the season may start earlier and end later. For instance, the Californian blackberry season starts in May and ends in October. 
Superstition in the UK holds that blackberries should not be picked after September 15th, as the devil has claimed them and left his mark on the leaves. There is some value behind this legend, since wetter and cooler weather often allows the fruit to become infected by various molds including Botrytis. These molds can give the berries an unpleasant flavor and make them toxic.