The tips of the canes on my blackberry bushes love to take root in the ground and start new plants. If a cane is allowed to do that, what effect does this have on the canes ability to actually produce berries in the spring?
This shouldn't reallt affect it at all, as this is what the plant does. That said, it may help to prune it back some to prevent the shrub from getting too big and spreading too much. These articles should help as well: https://www.gardeningknowhow.com/edible/fruits/blackberries/growing-blackberry-bushes.htm, https://www.gardeningknowhow.com/edible/fruits/blackberries/blackberry-pruning.htm If you are having ssues with non fruiting, this article may help: https://www.gardeningknowhow.com/edible/fruits/blackberries/blackberries-not-fruiting.htm
I live in San Diego, CA. Is there a special kind of those plants to get for a garden here?
You want to look for a blackberry or raspberry that has low chilling requirements for best results. Some varieties to look at are Brazos, Choctaw, Natchez, Navaho, Shawnee and Tupi.
I have blackberries and lots of daylilies. How do I organically control the large Green June Beetle? They are larger than Japanese beetles. Last year their infestation was so extensive, they ate my daylily blooms before they could even open. It was disgusting!
This article will help you with that:
https://www.gardeningknowhow.com/plant-problems/pests/insects/june-bug-beetles.htm
This is my first time growing blackberries and blueberries, and we bought 1 bush of each. I was told that you need at least 2 of each for them to produce fruit. I was just wondering if I needed to go out and get a second plant?
Generally, you want at least one plant of two different varieties for best pollination. It's not absolutely necessary though, if you'll be happy with a handful or two of berries. And there are some varieties that do well without another plant nearby. These articles should help you with growing them: https://www.gardeningknowhow.com/edible/fruits/blackberries/growing-blackberry-bushes.htm, https://www.gardeningknowhow.com/edible/fruits/blueberries/growing-blueberry.htm
I have been growing blackberry bushes outside my fence. This year it looks like the bushes are smaller and the leaves are brown. What should I do? Every summer we get delicious berries, but this year seems we aren't lucky.
It sounds like the plants may have a fungus, which would reduce their ability to fruit. Try treating the plants with a fungicide and this should help clear it up.
Two shoots have been led along horizontal wires. Fruit comes from offshoots of the two long arms. I'm not sure how to prune it now. Can I cut it right down to ground and start again?
I would not cut it all the way down to the ground, but you can cut it back significantly. Do you know the variety of blackberry? That will help with giving advice on how best to prune it.
I have a thornless blackberry patch that is way of control. Nothing has been done to the bushes since planting 5 years ago. How does one get this under control without starting all over? Thank you.
Here is an article that you may find helpful: https://www.gardeningknowhow.com/edible/fruits/blackberries/blackberry-pruning.htm