We planted and espaliered 2 semi dwarf apple trees 6 years ago, a Cox’s Orange Pippin and a Braeburn and neither has produced fruit. (well, one year we had 5 beginning apples on the Braeburn. ) In the spring, the trees have NO, or some years, a few flowers, and during the summer they produce numerous and vigorous water sprouts. The trees were planted in well amended and watered soil but since then have not been fertilized nor watered. We are trying to slow the water sprout growth. For 4 years we left the sprouts until winter before pruning. However, the last 2 summers we have pruned the sprouts around end of July but they (especially the more vigorous Braeburn on the right of the photo) replace the sprouts quickly and vigorously. We are ready to replace the trees with single Italian prune plum but would like to understand the problem better before trying with another fruit tree. We have a Sergeant’s crab apple nearby that flowers and fruits happily and a kiwi that started producing in year 4 as promised. Because these apple trees were/are so heavily pruned, they produce the sprouts in reaction, yes? We have looked at plenty of other espaliered fruit trees which do not look like ours. Many thanks for any ideas or thoughts. In photo: Take Sept 11, 2018, 6 weeks after removing the first lot of sprouts. and having just removed the sprouts from the lower left quadrant of the Braeburn on the right. (to try to show the structure of the tree).
I'm not sure why your trees are not producing fruit; but trees without fruit grow more vigorously, which would explain why they are producing so many water sprouts. It's too late this year; but next spring, when the new growth is 4 to 6 inches long, you could try girdling the main trunks of one or both trees. This requires cutting a ring about 1/8" wide completely around the circumference of the trunk, below all side branches. The bark and cambium layer must be completely removed within the ring. I successfully used this technique to increase blooming and fruiting on a large apple tree that I was pruning heavily to reduce its size.
Since the reason for these apple trees not producing fruit remains unknown, girdling them seems a pretty drastic first measure to solve the problem. Wouldn't the trees die above the girdle? You don't say how far from the ground the operation should be performed but I picture trees effectively cut down to about 12 inches (30 cm) from the base. Why not just cut them off instead of girdling? I am obviously missing something. More information about this strategy can be found on the web on sites such as How to Girdle Fruit Trees PScott - I hope you will let us know how your apple trees perform in future.
Margot, a narrow girdle doesn't kill the tree, it just cuts off the flow of nutrients through the phloem tissues for a while. This reduces new growth, enhances fruit set, and increases flower bud formation for the following year. The narrow strip is covered with new tissue in a month or two. It should only be applied to trees growing vigorously, which is the case here. There is a less drastic method, called scoring, which just requires a knife incision around the circumference of the tree trunk. I haven't tried it, but I suspect that it would be less effective than girdling. I've tried girdling using widths up to 1/4" on apple, peach, and cherry trees without inflicting any damage. I also girdle all of my grape vines every year because it results in larger and earlier grapes.