Call your local county extension agent's office, which may be listed under Deptartment of Agriculture. This person may be the best resource for your plant-finding mission. The agent can tell you everything you'll need to know about growing blackberries in your area. You'll need to know whether or not commonly retailed blackberry bush plants grow well locally. The agent may be able to give you specific cultivar names and types that will perform best. Find out about soil requirements, such as pH levels, and amendments like organic compost. They may ask you to submit a sample of your soil as a means of helping you grow your plants. Ask about any known growers in the region. If by some chance the extension personnel cannot give you the answers you seek, often growers are happy to share information with backyard gardeners.
Call or visit local retail nurseries. Most of them have resident plant gurus who are knowledgeable and helpful. Personnel may even be successfully growing what you're looking for in their own backyards. Even if you don't see blackberry bush plants on their shelves, talk to them. Just because the plants aren't there at the moment doesn't mean they won't be in the future. Or they may be able to direct you to a retailer who does sell them. The biggest advantage of buying locally is that the varieties available are apt to be suited to your region.
Talk to any friends nearby who are growing blackberry bushes. If they purchased their plants, it's likely they'll remember the names of their cultivars, where and when they were purchased and how much they cost. You'll probably be able to see adult producing plants in action, and your friend's comments and recommendations about them can be invaluable to you.
Take the knowledge you've gathered and study it to determine which varieties are most suitable for your situation. Take into consideration how much time you'll have to expend on your blackberry plants. If your time is limited, you might need to choose highly disease- and pest-resistant varieties such as Brazos, Cheyenne, Ebony King, Natchez, Navaho and Smoothstem. These will require less maintenance time and effort. If you don't like thorns, select Apache, Arapaho, Loch Tay, Natchez, Navaho, Ouachita, Smoothstem and Thornfree. If the flavor of the fruit is the most important thing to you, pick from the tastiest types, which are considered to be Arapaho, Black Satin, Chester, Cheyenne, Comanche, Ebony King, Eldorado, Jersey Black, Olallie and Triple Crown. Estimate how many plants you'll need to populate the prospective planting site. Typically, you should figure on spacing blackberry bushes three to five feet apart.
Shop local retailers during blackberry planting times, which is when they'll most likely be in stock. Blackberries can safely be planted anytime from mid-October through March, depending upon your location, with the best choice in spring. The soil should still be a little warm and quite workable. As long as it isn't soggy or frozen, these plants will do just fine. Inspect plants that you are considering carefully from all angles. They should have an overall healthy appearance. Scrutinize all surfaces of the stems and leaves. Reject any plants that are discolored, spotted or splotched, yellowing, broken, damaged or wilting. Don't accept specimens with roots growing out of the bottom of the container. Those are pot-bound, and their growth may have been retarded. If you see any bugs or white fuzzy stuff, walk out and find another supplier.
Buy from mail order or online retailers if you find no healthy, young blackberry bush plants in your region. Reputable suppliers offer various replacement guarantees on everything they ship. The larger companies that have been in business the longest are typically the best choices. Although their prices may be a little higher than others, you're far more likely to be satisfied with your experience with them.