Blue Berry Production
Hello I have a number of mature blueberry plants that are more than 10 years old and about 4-5 feet tall. For some reason several of the plants produce relatively small berries. I do prune them annually and fertilize with ammonium sulfate fertilizer and take soill tests every few years. Is there any way I might try and increase the berry size? Secondly, several of the plants send up long leggy branches that only have vegitation /berries on the very top - and these same branches fall over and lay on the top of accompanying lants. I may have planted these plants too close together years ago . Any recommendations for resolving these production related issues?
There is a noticeable range of sizes produced by the different blueberry varieties. Some of your blueberries may naturally be smaller. Other than that, be sure to water during dry spells, as blueberries are shallow rooted, so that the berries can swell to a normal size for them.
The long shoots of new wood you describe could be exaggerated by the pruning and fertilizing. New, first year shoots do not to produce fruit. You must let them remain for a few years to enjoy consistent harvests. If they soar our of reach, prune them back so you can reach them. Please read through the pruning instructions on our website. There are many factors to consider. Blueberries require little pruning but as our webpage notes, there is great variation in growth rates so pruning must be tailored to your specific plants and site. http://extension.umd.edu/growit/fruit-profiles/blueberries Pruning can increase berry size.
Also read through the fertilizing instructions. Too much fertilizer can stimulate lush, overly-vigorous and weak growth. (Also growth more susceptible to disease and insect problems.) The fact that the long shoots are falling over suggests cutting back on fertilizer.