Q. In the last few months, we purchased property that included a portion of an old blueberry farm. We did have some of the bushes removed to have more backyard; however, we still have over 1,000 bushes that haven’t been touched for about three years! Most of the bushes are between six to seven feet high. Just a couple of rows are about four feet. Should we prune or cut down these bushes so they will still grow well in the spring? We were thinking that January would probably be a good time to prune, but, of course, we are looking for your guidance on this.
A. Fortunately, blueberries are relatively undemanding compared to many other fruit crops. Each year, the blueberry plant produces new stems from the base as well as lateral twigs from existing stems. The younger stems should be the most productive, if they aren’t shaded out by older growth. The difference in size that you’ve observed between different sections may very well be due to difference in variety; some mature at around four feet while others reach five to six feet. Late winter is the ideal time for pruning.
Since it’s been about three years since they were last pruned, the plants would likely benefit from a bit of renewal pruning. First, assess the overall health of each plant and remove any dead or damaged stems. Next, remove about one-third to one-sixth of the oldest, largest-diameter stems completely down to the ground. For example, if an individual plant has 20 main stems coming from the ground, remove three to six of the largest-diameter stems completely back to the ground. You can thin out the lateral branches on the remaining main stems, if needed, but that’s very tedious work, given the number of plants you have to deal with.
If they are more severely overgrown, then you could actually cut the entire plant down to nearly ground level to force it to grow all new stems. There, of course, would be no harvest that season.
You’ll find information about fertilizing blueberries in Purdue Extension Bulletin http://www.hort.purdue.edu/ext/HO-65.pdf. Additional information on managing large blueberry plantings can be found in the Midwest Small Fruit Pest Management Handbook http://ohioline.osu.edu/b861/.
Q. I have a persimmon tree that I want to take starts off of. What is the best way to do this? I have tried starting seeds with no success. I have also dug up canes from around the tree. With their taproot, I have had little success. Can these trees be started from cuttings? If so, how?
A. Persimmon can be propagated by seed, though the mature seed will need a period of moist chilling to allow the embryo to fully develop. Pack the seed into moist sand, peat moss or vermiculite and store at 40-50 F for 60-90 days. Or you could try planting the seed outdoors in fall, and let Mother Nature provide the moist chilling. Place a thick mulch layer over the seed bed after the ground has frozen. Named cultivars are propagated by grafting onto seedling rootstock, because persimmon does not breed “true” from seed. Stem cuttings are not particularly successful for persimmon, but root cuttings can be used. You’ll find more information in the Purdue Extension publication “Persimmons” at http://www.hort.purdue.edu/ext/HO-108.pdf.