Answer: You can indeed grow the beach plum in your yard. Plant 1-2 year old whips in sping, and space them at least 20' apart. Don't let the soil dry out, watering moderately and
consistenly throughout the season. Provide a couple inches of compost as a mulch around the young plants, and cover it with straw or other mulch.
Pruning in the early years of a plum tree's life should be focused on training it to a strong modified-central-leader form. What you are aiming for in pruning is strong, lateral branches that are well spaced for sun and air exposure and have a sturdy branch angle from the main trunk (between 50-80 degrees). I can recommend the Cornell University website where you can order a low-cost bulletin that covers cultural and pruning basics for plums and other fruit: http://www.cce.cornell.edu/publications/fruit.html/. Pruning is a skill that is best learned with the help of diagrams - it's safer for the trees, too!
Here are a couple of sources for you to try:
Kelly Nurseries, 410 8th Ave. NW, Faribault MN 55021, ph# 507/334-1623 or Oikos Tree Crops, PO Box 19425, Kalamazoo MI 49019, ph# 616/624-6233. Enjoy!
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