Posted by Brent Wilson on 8/16/2016 to Fruit Gardening
If you're looking for edible plants that are easy to grow and harvest definitely consider thornless blackberries. They are self-fertile so all you need is one plant to produce fresh blackberries.
Here's a breakdown of what you need to know...
Blackberry plants grow best in an organically rich, well-drained but moist soil. They do not like a constantly soggy or wet soil which can cause root rot or other harmful plant diseases.
How To Test Soil Drainage
If you are uncertain about soil drainage in the area you intend to plant your shrubs, it's well worth taking the time to test the drainage before planting. To test soil drainage, dig a hole 12" wide by 12" deep in the planting area. Fill the hole with water and let it drain. Then, after it drains, fill it with water again, but this time clock how long it takes to drain. In well-drained soil the water level will go down at a rate of about 1 inch an hour. A faster rate, such as in loose, sandy soil, may signal potentially dry site conditions. A slower rate indicates poor draining soil and could be a caution you might need to improve drainage, plant in a raised mound or bed, or look for plants that are more tolerant of wet or boggy conditions.
Blackberry plants grow best in a moderately acid to neutral soil ranging between 5.8 to 6.8 on the pH scale. Most average garden soils fall between a pH range of 6.0 to 7.0.
Testing Soil pH
Soil pH is a measurement of the alkalinity or acidity of soil and is measured on a scale of 1-14, with 7 as the neutral mark. Any measurement below 7 indicates acid soil conditions, and anything above 7 indicates alkaline. If you're unsure about the pH of your soil, or whether or not it is suitable for growing Blackberry plants, it's a good idea to test the pH in the planting area. You can quickly test soil pH with an inexpensive soil pH tester probe. To raise the pH (make more alkaline) you can add pelletized limestone to the soil. To lower the pH (make more acid) you can apply Soil Sulfur, Aluminum Sulfate, or Chelated Iron. Adding organic compost to the soil or using compost as mulch can also help to increase acidity and maintain acid soil conditions.
Learn More: What is Soil pH and How To Adjust It?
Blackberry plants grow and produce the most fruit in full to mostly sun, however will produce a good crop of berries even in some shade. We suggest at least 6 hours of direct sunlight per day during the growing season.
How To Plant A Blackberry Bush
When growing as a hedge, space both erect and semi-erect blackberry plants 3 feet apart in the row, with 8 feet between each row. Space plants 8 feet or more if you want space between your plants.
Tip For Bareroot Plants: 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, the tops of bare root 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.
Start by digging your planting hole at least three times as wide and as deep or not much deeper than the root ball of your plant, or 18 inches wide if you are planting a bare root plant. The wider the hole the better. Place native soil removed from planting hole around the perimeter of the hole, in a wheel barrow, or on a tarp.
Depending on the type, fertility and porosity of the soil in the planting area, it may be beneficial to amend the native soil. When planting in heavy clay soil mix in a good, compost, soil conditioner or planting mix at a 50/50 ratio with the soil to enhance porosity and ensure good drainage. When planting in a sandy or quick-draining soil, amending with top soil, organic compost, and/or peat moss will help to retain moisture and supply vital plant nutrients. When planting in a fertile, loamy, well-drained moist soil there may not be a need to amend soil.
To remove your blackberry plant from the container it was growing in, firmly grasp the base of the plant and very gently try to lift and remove it from its container. If the root ball is stuck in the container either cut the container away or place the plant on it's side and gently pound on the side of the container to loosen the root ball. After having removed the plant from the container, loosen some feeder roots around the surface of the root ball. If root bound, you can gently spray the sides and bottom of the root ball with a stream of water from a garden hose. This will help to wash away some soil from the exterior of the root ball making it easier to loosen roots.
Set your blackberry plant in the planting hole so that the top edge of the root ball (or the crown of the bare root plant) is at or slightly above ground level to allow for settling. It may be necessary to place some of your backfill soil mixture in the bottom of the hole to achieve proper planting height.
After setting your blackberry plant in the planting hole, use one hand to hold the plant straight while using your other hand to begin backfilling the soil mixture around the root ball, tamping as you go to remove air pockets. When you have filled the hole to the halfway point you can soak the soil. Then continue backfilling to the top edge of the root ball. To avoid suffocating your plant, do not put any soil on top of the root ball.
Step 6 (Optional)
When planting your blackberry plant in a location that is far from a water source, you can use remaining soil mixture to build a water retaining berm (catch basin) around the outside perimeter of the planting hole, as shown in the diagram above. This basin will help to collect water from rainfall and irrigation often reducing the need for hand-watering. The berm can be removed after a year when the plant has established itself.
Next, deeply water the planting area, including the root ball, to a depth equal to the height of the root ball. For an extra boost, to stimulate early root formation and stronger root development, you can also water you newly planted blackberry plant with a solution of Root Stimulator, which reduces transplant shock and promotes greener, more vigorous plants.
To conserve moisture and suppress weed growth, apply a 1 to 2" layer of pine bark mulch, a good organic compost, or a 3-4" layer of pine straw around your newly planted blackberry plants. As the mulch decomposes it will add vital nutrients to the soil that your plant will appreciate. Avoid the use of freshly chipped or shredded wood for mulch until it has cured in a pile for at least 6 months, a year is better. Avoid placing or piling mulch directly against the base of the shrub as this could cause problems with the bark.
Trellising Blackberry Plants
Erect or semi-erect Blackberry plants do not usually need a trellis for support. That being said, heavy crops of berries can weigh canes down. A trellis or fence can be an extra-added measure of support. If needed, you can install a simple one-wire trellis system to help support plants.
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 a mark on each post at 4 feet above the ground. Using staples or u-nails, attach 9-gauge 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.
Plant Long & Prosper!™
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