Gadenin日本語Get the appPut the posts and wires in before the plant
A blackberry is not a bush. It is a permanent crown that throws long flexible canes every year, and those canes have to be tied to something or they lie on the ground, root at the tips and turn the bed into a thicket. Driving posts in later, once the crown is established, means digging next to shallow roots and cutting them. Do it first, while the ground is empty.
Two posts at the ends of the row, sunk at least 24 inches (60 cm) and braced, carry three horizontal wires at 3 feet (90 cm), 4 feet 6 inches (1.4 m) and 6 feet (1.8 m) above the ground. Use straining wire, not garden twine: a fully loaded cane wall is heavy, and wet foliage in a summer gale pulls hard. If the row is longer than about 15 feet (4.5 m), add an intermediate post so the wires do not sag into the fruit.
Leave at least 3 feet (90 cm) of clear standing room on the picking side of the wires. You will be reaching into the wall repeatedly for six weeks, and a path narrower than that means picking with your face in the canes.
Choosing the site, and why thornless is worth it
Blackberries crop in full sun and tolerate part shade better than most fruit, but shade costs you sugar rather than yield. A plant on a north-facing wall will still fill with fruit and the fruit will still be tart in a poor summer. Give the row six hours of direct sun where you can, with air moving through it, and keep it off ground that stands wet in winter.
Thorny and thornless plants grow and crop the same way, but they are not the same job to own. A thorny cane hooks into skin and clothing every time you tie it in, and winter pruning a thorny plant is genuinely unpleasant work done in thick gauntlets in cold weather. Thornless plants let you handle canes bare-handed, which means you actually do the tying-in on time instead of putting it off. If you are choosing now, choose thornless; the fruit is the same fruit.
| Site factor | What blackberries want | What goes wrong otherwise |
|---|---|---|
| Light | Six hours or more of direct sun | Fruit stays tart and ripens unevenly along the cane |
| Drainage | Free-draining soil, never standing wet | Crown rot; canes wilt in midsummer with fruit on |
| Soil pH | 6.0 to 6.8 | Yellow leaves with green veins on chalky ground |
| Space | 8 to 12 ft (2.4 to 3.6 m) of wire per plant | Canes overlap, the middle shades out, mold spreads |
| Access | 3 ft (90 cm) clear path on the picking side | Fruit at the back goes unpicked and rots on the cane |
Spacing and planting depth
Space plants 8 to 12 feet (2.4 to 3.6 m) apart along the row. That looks ridiculous when you are holding one dormant stick, and it is correct: a single established crown throws five to eight canes each 10 to 15 feet (3 to 4.5 m) long, and they all have to go somewhere on the wires. Planting at 4 feet (1.2 m) apart, which people do constantly, gives you a solid green mass by the third year with fruit only on the outside of it.
Plant bare-root crowns in the dormant season, any time the ground is neither frozen nor waterlogged; container-grown plants can go in whenever the soil is workable, but they establish best dormant. Set the crown so the old soil mark on the stem is level with the surface, roots spread out flat at about 3 inches (8 cm) deep. Blackberry roots run sideways, not down. Firm the soil, water in hard even if the ground is damp, and mulch 2 inches (5 cm) deep with compost, keeping the mulch off the crown itself.
- Cut the planted cane back Once the crown is in the ground, cut whatever top growth came with it down to about 10 inches (25 cm). The stub is only a marker. The canes that will crop for you come up from the crown later in the season, and leaving the old top on makes the plant try to fruit in its first year instead of building roots.
- Stop tip rooting at the edges Sink a physical edge, a board or heavy membrane 8 inches (20 cm) deep, along any side where the row meets a lawn or path. It will not stop a cane tip that arches over it, but it stops the crown creeping sideways and gives you a clean line to hoe against.
- Water through the first summer A new crown needs 1 to 2 gallons (4 to 9 liters) a week through its first dry spell, poured slowly at the base. First-year failure is almost always drought at the crown, not cold, and the plant gives no warning until the new canes stop extending.
Write down what you planted and where
Record the planting season, the exact position of each crown along the wire run, and whether the plant is thorny or thornless. Three years in, when the row is a continuous wall of cane, you will not be able to tell where one plant ends and the next begins, and you will need to know which crown a struggling section belongs to.
Also note the date the first new cane broke ground. That single figure is the most useful thing in the file: in later years it tells you at a glance whether the plant is running early or late, which is how you decide when to start tying in rather than working from the calendar.