Blackberry
Blackberries are the dark purple-black fruits of several species of Rubus. They grow on prickly canes and are often found in the wild. The fruit is not a true berry. It’s more accurately called an “aggregate fruit,” because it is a cluster of many small fleshy fruits (called drupelets) that each develop from separate ovaries. Blackberries can be easily confused with raspberries, but the latter (including black raspberries) have a hollow centre, while blackberries have a greenish-white core. The other way to tell them apart is by looking at the leaves: raspberry leaves are silvery on their undersides, whereas blackberry leaves are light green. Both plants are members of the same genus (in the rose family), and related species are known by a variety of other names, including bramble, dewberry, and thimbleberry.
Health Benefits
Blackberries have one of the highest antioxidant levels of all fruits, based on their ORAC value. (ORAC stands for “oxygen radical absorbance capacity,” which measures the ability of a food to clean up the mess left behind by free radical damage—oxidative stress—in the body.)
If you want to slow down the aging process, blackberries can help promote the healthy tightening of tissue, a non-surgical procedure that can make skin look younger. Prolonged consumption also improves clarity of thought and memory. The fruit contains anthocyanins, salicylic acid, and ellagic acid, which are all heart- and brain-healthy.
The plant’s root, bark, and leaves are also packed with tannins, which have historically been used as an astringent, a tonic for diarrhea, and a treatment for whooping cough.
Blackberries are rich in bioflavonoids and contain soluble and insoluble fibre. One cup of blackberries has nearly 8 grams of fibre and contains half the daily recommended dose of vitamin C, which protects the immune system and can lower the risk of developing certain cancers.
DIFFICULTY
Easy to medium
HARDINESS
Perennial in zones 5 to 8
TIME TO PLANT
Spring or early fall
TIME TO HARVEST
Late spring to early fall (depends on variety)
LOCATION
Full sun
SOIL TYPE
Moist, well-drained
Growing
Blackberries are easy to grow, but they are not maintenance-free and they require space. Like raspberries, the canes are not only vigorous, but may be invasive. You need to be willing to spend time pruning them to prevent them from spreading to other areas in the garden.
Common Varieties: Varieties abound, but they can be broken down into three types: training, erect, and semi-erect. Training blackberries are not hardy in cooler climates. Erect varieties (‘Darrow’, ‘Cheyenne’, and ‘Illini Hardy’) produce fruit with larger seeds on old wood, and the canes are self-supporting. Semi-erect varieties (‘Chester’, ‘Triple Crown’) require staking and produce higher yields on thornless canes.
PLANT
Plant in early spring or as soon as soil can be worked. Blackberries can be planted in most soil types, including clay, but they enjoy well-drained soils rich in organic matter. Canes can last up to 15 years if you regularly amend the soil to replace much-needed nutrients (my favourite addition is sheep manure).
Plant blackberries in full sun and leave lots of space between them; depending on the variety that can mean 0.5 to 2 metres (2 to 6 feet). Plant at the same depth as the pot they came in. Blackberries are not the most attractive plant, so they should probably go at the back of the landscape. Plant in groupings or rows, and avoid planting them next to raspberries to minimize the spread of viruses.
Aphids are a threat to blackberries, but never fear, Mother Nature is here! To minimize the threat of these pests, improve the environment for ladybugs, which eat aphids. You can purchase ladybug lures to encourage them to visit your garden, or even buy the ladybugs themselves.
Blackberry blossoms and then unripe fruit. Blackberries look nearly identical to black raspberries but are often slightly rounder in their shape.
GROW
Growing blackberries isn’t rocket science. It takes regular weeding, occasional watering, annual soil amendment, and early-spring pruning. Most blackberries produce fruit on last year’s growth (old wood), so the only canes that should be removed in early spring are those that produced fruit last season (as well as any dead canes). You’ll be able to see where you picked last year’s fruit: these canes will probably be thicker than the new growth. Canes that emerge this year will produce next season.
As a general rule, remove the canes of erect blackberries immediately after harvest. In spring, remove any dead or weak canes, selecting the healthiest 8 to 16 canes for staking.
Monitor blackberries for signs of insects or disease, including spider mites, aphids, beetles, rusts, or blights. Identify the specific problem and treat as necessary, but be aware there are few organic controls for disease.
HARVEST
Depending on the variety, blackberries can be harvested from late spring all the way into early fall. Harvest them when the colour appears deep black; if the fruit is red or purple, it’s not ripe. Don’t forget to reach between the canes to locate ripe fruit hidden by foliage. Pick late morning and avoid harvesting midday.
STORE
Don’t wash the fruit until you are ready to use it. Store blackberries uncovered in the refrigerator for up to a week, depending on the initial quality. After a few days in storage, however, the fruit loses its bright colour and fresh flavour and tends to shrivel. To freeze blackberries, wash, drain, and freeze on a baking sheet before transferring to resealable bags. Blackberries can also be preserved in jams and jellies.
Put It to Work
Canker sores? Chew blackberry leaves!
Chewing fresh blackberry leaves can help canker sores and inflamed gums. Chewing releases the astringent tannins, which heal and soothe the mucous membranes of the mouth. It also releases vitamin C, which is essential for gum health. Just pop a carefully washed handful into your mouth and chew for a couple of minutes. Spit out the leaves when you’re done.
Inflamed gums? Gargle with blackberry!
If you’re not a fan of chewing leaves (see above), they can also be brewed to make a refreshing cup of tea. They carry a slight bitter taste, so you’ll want to add manuka honey, which also improves oral health. Place about 10 leaves in a mug, pour boiling water over them, cover, and steep for 10 to 15 minutes. Swish the tea around your mouth a few seconds before swallowing—the astringent tannins are also effective as a gargle or mouthwash.
High blood sugar? Make blackberry jam!
If you’re watching your sugar levels, jam may not be your best choice. But if you can’t give up a smear of fruity goodness on your toast in the morning, replace your super-sweet strawberry jam with this low-sugar blackberry jam.
2 cups blackberries (fresh or frozen)
2 cups granulated sugar
Freshly squeezed juice of 1 small lemon
Using the back of a spoon, press the blackberries through a fine-mesh sieve (to remove the seeds), letting the juice and pulp drain into a pot. Stir in the sugar and lemon juice. Cook over high heat for 5 minutes, then reduce the heat to medium and cook, stirring occasionally, for an additional 15 minutes. Skim off the foam with a slotted spoon and discard. The jam will thicken as it cools. Store in a resealable glass jar (like a Mason jar) in the refrigerator for up to 3 weeks.
Fast Forward
Fast forward to the health food store to purchase Celebration Herbals blackberry leaf tea or equivalent. Follow the instructions on the label.
Cautions
Blackberries have no known interactions or harmful side effects.