If you're looking for edible plants that are easy to grow and take up little space, definitely consider blackberries. They are self-fertile and so will produce fruit even if only one plant is grown.
Best Growing Conditions...
The best and most berries will be produced when blackberry plants are growing in full sun. However, where space is limited, a blackberry cane will produce good crops even when grown in shade, which is something no other common fruit plants will do. Blackberries produce their flowers very late in the season so frost is usually not a problem.
Soil - Blackberries will grow reasonably well in most soil types except for very compacted clay or light chalky soil. In these soils it'll be worth your time to mix in lots of organic compost to condition the soil and add beneficial nutrients and bacteria plants need to grow healthy. Blackberries grow and produce the best fruit in well-drained but moist fertile soil that is rich in organic matter. They like the soil to hold a good supply of water, especially when the fruits are developing in summer, but not so much water that the soil stays constantly soggy or wet.
Backberries do best in a acidic soil at 5.5 and 7.0 on the pH scale. It's a good idea to test the soil for pH. Testing kits are available at most local nursery and garden centers or you can buy soil test kits online here. Your local Extension Service might provide soil testing services as well. Depending on the results of the soil test, you can add lime to raise the pH or soil sulfur to lower the pH (make more acid).
When To Plant A Blackberry
Bareroot blackberry plants should be planted in late winter or early spring. Container-grown plants can be planted year round. Roots of blackberries are very sensitive to light so it's best to plant them on a cloudy day.
Building Trellises for Blackberries
If you choose to grow your blackberries on trellises, there are two types of blackberries: Erect, and trailing, and each requires a different type of trellis. During the first year it is not necessary to train the blackberry canes to the trellis. Starting the second year tie the canes to the trellis. Loosely tie the canes to the wire as they develop. The best time to do this is before the buds start to swell in early spring.
Trailing Blackberries
If you are planting trailing varieties of blackberry it will be necessary to provide support to keep the canes off the ground. Blackberry trellises are simple and inexpensive to build. Sink two 8-foot pressure treated 4x4 posts about 3 feet deep in the ground at anywhere from 10 to 20 feet apart. In sandy soil you'll need to add a quick-setting mortar mix to anchor the posts. In more dense soils just tamp the dirt down around the post. Make two marks on each post, one at 2.5 feet above the ground and the other at 4.5 feet above the ground. Using staples or u-nails, attach 9-guage coated wire at the posts where marked. Before attaching, wrap the wire one or two times around the post. Make wire as tight as possible.
Erect Blackberries
Erect can be grown with or without a trellis as a hedge or shrub border. If you build a trellis for erect blackberries it can be a single-wire system.
Spacing
How far apart you space plants will depend on the type of blackberry. It's best to follow spacing instructions on the plant label/tag or consult with your local nursery and garden center professional or Extension agent. There are basically two types of blackberries:
Erect - Erect varieties have stiff canes that are upright and arching. In general, these should be spaced 2 to 4 feet apart, depending on the variety.
Trailing - Trailing blackberries have flexible canes that must be tied to a trellis or fence so they don't flop to and lay on the ground. In general, these should be spaced 5 to 6 feet apart.
How To Plant A Blackberry
The planting methods for blackberry will vary slightly depend on if the plants are bareroot or container-grown.
If your plant is bareroot: Shake the packaging material off the roots and then soak the roots in a bucket of water for several hours before planting. This keeps the roots from drying out, which you definitely don't want to happen. This is one reason I prefer container-grown blackberry plants. Also, bareroot plants should be cut back to about 6-8-inches. This helps plants to direct their energy to developing a strong root system during the first year, which makes plants healthier and more productive over the long run. On the other hand, container-grown plants in 1-gallon or larger size containers are usually 2 or more years old and do not need to be pruned at planting time.
Step 1 - If you are planting blackberries in a row, the soil can be tilled to 8 to 12 inches deep in a band at least 3 to 4 feet wide. If the planting site stays consistently soggy, plant on raised beds or mounds 6 inches or more in height and several feet wide to ensure good drainage. Otherwise, if you are planting an individual bareroot blackberry plant in the ground without tilling, dig a hole wide enough to accomodate the roots without crowding them. To plant a container-grown blackberry, dig a hole two to three times as wide and a few inches deeper than the root ball. Place dirt removed from the planting hole around the perimeter of the hole.
Step 2 - If your soil is fertile and well-drained there is not a need to add compost or soil conditioner. If your soil is heavy clay or not very fertile, thoroughly mix oragnic compost such as composted cow manure or mushroom compost at a 50/50 ratio with the native soil removed from the planting hole.
Step 3 - If planting a container-grown blackberry, remove the rootball from the container and set the plant in the hole with the top edge of the rootball at or slightly above ground level to allow for settling. Bareroot plants should be set in the hole so that the crown is at ground level.
Step 4 - While holding on the the plant use your other hand to start pulling your backfill soil around the roots, gently tamping as you go to remove air pockets. When hole is three-quaters full of soil pour a gallon or so of water into the hole. Finish backfilling, lightly tamping as you go, and then water thoroughly.
Step 5 - In the absence of a soil test, fertilize with a well-balanced, non-burning, organic plant food at planting time, following instructions on label.
Step 6 - Mulch around plants with one- to two-inch layer of pine straw or shredded wood mulch. This helps to conserve water and prohibit weed growth.
Happy Blackberry Growing!
