They say that you should not pick the fruit the first year, but I have harvested some the first year. It usually works out ok. Be sure to
weed the plants well, and a heavy mulching works well too. It will hold the moisture in during the heat of summer and keep
weeds from choking the plants.
I did not have bush berries, so I had to look up the care for your type.
Here is some of waht I found in my research:
Blackberry bushes grow fast. Some can produce 40-foot canes. Blackberries need well-drained, fertile soil and a pH level of 5.5 to 6.5. Amend the soil if necessary. Plant your blackberry bushes in full sun to partial shade for best berry production.
Trellis trailing blackberry bushes on 12-gauge wire strung between wood or metal posts spaced 20 feet apart. Place the top wire 5 feet from the ground and the second wire 18 inches below it. Spiral the canes up the post and along the wires.
Lay 2 inches of mulch around bushes to prevent
weeds. Use bark nuggets on slopes and hillsides to keep mulch from washing away. Mound mulch around trailing blackberries after the bush goes dormant to protect from harsh winters.
(I used well dried grass under mine, it is cheap & works well.)
Give blackberry bushes 1 inch of water at each watering during the
growing season. Give them extra water during high winds and heat waves. Avoid fruit rot by watering close to the roots.
Spread a 10-20-20 fertilizer 1 foot away from the roots in a shallow trench that's 3 to 4 inches deep. Blackberry bushes have shallow roots and may burn if fertilizer is applied to close to roots. Follow package directions closely.
Prune bushes to clear dead wood and promote blooms. In late fall, cut all dead floricanes--(the canes that produced the berries)--to the ground. Don't prune the new growth--the primocanes--as they will produce the following year. In early
spring, before the bush leafs out, cut back new berry-producing floricanes to 18 inches. In the summer, trim 2 inches off developing primocanes when they reach 3 to 4 feet tall to promote new growth