Plump, ripe blackberries are very perishable, but a great treat on a hot summer day.
When I was a kid, one of the treats of summer was raiding the wild blackberry patch. My cousins and I would descend on a patch at the edge of my grandfather's farm field and eat until our mouths, lips and shirts were stained deep purple. What fun!
Of all the bramble crops you can grow, I've always thought of blackberries as the wildest. For years, even the cultivated varieties seem just a step away from the patch growing in an abandoned field. But even this quintessential wild fruit has become tamed by breeders. There are now blackberry varieties without thorns and new ever- bearing varieties that produce crops in fall and summer.
Like all brambles, blackberries are easy to grow and quick to produce a crop. Within one year you'll be rewarded with buckets of ripe berries. They are versatile plants that thrive in part or full sun, less than ideal soils, and require little care. Actually, one of the problems of blackberries is they grow too easily. They love to spread and can invade other nearby plantings.
The berries themselves are highly perishable, so eating them soon after picking is important. Not only are blackberries loaded with vitamins (one cup contains 50% of the RDA for vitamin C), they are one of the top berry sources of the antioxidants that fight cancer. So, whether it be for making pies, jam, juice or just eating out of hand, grow a row of blackberries for a tasty mid- summer treat.
Blackberries grow and thrive anywhere other brambles, such as raspberries, grow. They like mild springs and cool summers. Blackberries are less winter hardy than raspberries, so careful selection of varieties and planting site is important for northern gardeners. While the traditional summer bearing, thorny varieties are still the norm, newer thornless and everbearing varieties are expanding the berry growing range and taking some of the bite out of growing this crop. Like raspberries, the everbearing varieties produce fruit from new canes in fall the first year and then again on those same canes the next summer. This allows northern gardeners who may normally have trouble overwintering blackberries to still enjoy a crop.
Wait until blackberries are deep purple colored to harvest for the best flavor.
There are also trailing varieties of blackberries that are less winter hardy than erect and semi-erect varieties. They are mostly grown on the West Coast. Examples of these include boysenberry, loganberry, marionberry, and olallieberry. While erect and semi-erect growing varieties produce canes up to 7 feet tall, trailing varieties have canes that grow to 15 feet long and mostly (except loganberry) are thorny and wild growing. And as any Pacific Northwest gardener knows, they can quickly take over the universe if left unattended.
Here are some of the best erect and semi-erect varieties to try in your garden. All are hardy to USDA zone 5, unless otherwise noted.
'Black Satin' – This heavy yielding, thornless variety has semi-erect canes that are disease resistant and produce heavy yields. However, it's not suited for the Gulf Coast and Deep South.
'Brazos'' – A semi-erect, vigorous caned berry with yields of large fruits. Best on the Gulf Coast and Texas.
'Chester' – This thornless varieties is resistant to cane blight and produces large, sweet berries.
'Illini Hardy' – One of the hardiest blackberry varieties available. It produces tall, erect, thorny canes with medium-sized fruits. It's also disease resistant.
'Kiowa' – Hardy to USDA zone 6, these thorny canes are self-supporting and do not require a trellis. They are a good Southern performer.
'Prime Jim' and 'Prime Jan' – These new everbearing varieties produce erect, thorny canes with good quality fruit.
'Triple Crown' – A semi-erect, thornless varieties with sturdy, long canes and good quality fruit.
Blackberries can be planted in rows in the garden, or even along the side of the house and trellised vertically. They can grow more than 7 feet tall.
Like all brambles, blackberries grow best in full sun on well-drained, moist, but not wet, soil. Wet soils can harbor diseases that attack brambles. In part shade or less than ideal conditions, blackberries will still produce, but you’ll get a smaller crop. It's best to purchase certified, disease-free plants and locate them away from other gardens, decks, and patios. Blackberries love to spread and the fruit that drops can stain patio surfaces.
Although they're related to raspberries, the growth habit of blackberries is different and they should be planted in their own row. Semi-erect plants will need a trellis or support to keep the canes upright during fruiting, while erect plants can stand on their own.
Amend the soil with compost and remove any perennial weeds. Site blackberry rows ideally 1000 feet away from wild brambles. Insects often spread diseases such as viruses from wild berries to the cultivated ones. Plant blackberry plants in spring. Space plants 4 to 6 feet apart in rows spaced 8 to 10 feet apart. Keep areas between rows mowed to discourage weeds from encroaching on the berry plantings.
Water new plants well. Blackberries grow best in soils high in organic matter. Once established, mulch heavily with an organic mulch such as shredded bark, sawdust, pine straw, or straw. Fertilize in spring with an all-purpose organic product such as 5-5-5.
Support semi-erect and trailing berries by building a wire trellis similar to what's used for raspberries. Prune out broken, dead, or diseased canes anytime. Prune out spent fruiting canes (floricanes) in summer after fruiting is complete to allow room for the new primocanes to emerge and, if everbearing, fruit
In spring, prune canes so there are 5 to 7 large canes per plant, remove thin, spindly canes, and cut back the side branches on the large canes to 12-inches long to promote more bushy growth and fruiting.
Blackberries are susceptible to a number of soil-borne diseases. Avoid planting in any areas where tomatoes, potatoes, eggplant or peppers were previously grown in the last three years, since these vegetables can harbor soil-borne diseases that attack brambles.
Harvest in the morning when the air is cool. Select deep purple berries that drop off the plant easily when touched. Use a wide, shallow basin to collect the berries. Berries in the bottom of deep buckets will be smashed by the time you're done picking. Wear gloves and a long sleeve shirt to avoid the thorns on thorny varieties. Process the berries soon after picking. Fresh berries will only store for a few days in the refrigerator after harvest.