Plum tree

Some fruit trees develop alternating-year bearing. In a year of abundant fruit, so much of the tree's nutrients are devoted to producing fruit that little new fruitwood grows for next year's crop. In the following year with scarce fruit, ample nutrients are available to produce fruitwood for next year's crop.

Three things you can do to break this two-year cycle.

1. Prune the tree while it is dormant. Shorten new branches, and remove some older branches. You don't have to cut as severely as if it were a peach tree, but you want to cut enough to slightly reduce the amount of fruitwood.

1. Feed the tree well just as the flower buds begin to swell. Don't over-feed, but be generous. Feed again lightly after all fruit has been picked.

2. When fruits begin to form after flowering, remove about half of the immature fruit. Do this thinning when the fruit is about the size of small cherries, uniformly throughout the tree. Thinning should increase the size of the remaining fruit. However, the pits will not be any larger; and it's the pits that require extra nutrients. The fruit flesh is primarily carbohydrates, which are easy for a plant to produce. The pits contain protein and oil, which are more difficult. With fewer pits, more nutrients can be directed towards new fruitwood.

It can depend on a wide variety of things, not necessarily in this order:

proper pruning insect pollination weather, wind temperatures fertilizer/nutrients just plain luck

Some fruit trees produce a big crop every-other year alternating with a mediocre one.

gloria p

If this tree was on a standard rootstock, that might account for the delay in the earlier years of growth, but 20 years should have produced fruit sooner.

It may be a pollination issue. Have you or your neighbors recently planted any fruiting or decorative plum trees? Did you previously ever get blossoms that failed to turn into fruit? This variety is self-fertile, but I have seen problems with these kinds of fruits that are overcome with another identical variety, or a different variety nearby. Have you noticed a dearth of pollinating insects in past years?

Over fertilizing in previous years could have directed the tree to producing more growth rather than fruiting.

Could be several other things, but hopefully the current pattern will continue.

Sherwin