Fruit trees are not producing

(Question)

Can you tell me the possible reasons why my apple, pear and cherry trees have no fruit this year even though they all had numerous blossoms in the spring. I have noticed numerous gypsy moths in my garden. A Norway maple in particular has several branches which have been stripped of their leaves.

(Answer)

Thank you for asking your question about why your apple, pear and cherry trees have no fruit this year even though they all had numerous blossoms in the spring. You also asked whether the gypsy moth could be one of the problems.

Well, it’s definitely a shame that you’ve hit a patch of bad luck with your fruit trees. You did not mention some details which may have helped us tie down the answer such as how old your trees are, how many there are, what varieties you are growing, where you are living, and what your soil is like. So, I will need to be more general in my answer and hope this is helpful to you. The best place to start is at the beginning. Going back through previous questions answered by the Toronto Master Gardeners on this problem, I have found a mine of information.

There are six basic needs for healthy fruit tree development.

  1. First, fruit trees must be of a certain age before they produce. Depending on the type, and variety, this can vary from 3 to 7 years. Try to identify the variety of your trees, and then check the specific fruiting age for each.
  2. Pollination is key: trees require pollination to be able to set fruit. If any tree is not self-pollinating, it needs a compatible pollinator planted nearby. Hence, pollinators like bees, birds, and wind need to be present. Regarding self-pollinating, or not, tree ID will be necessary, since some are self-pollinating and others need another tree like a crab apple for cross-pollination.
  3. Weather hardiness: fruit trees need a sufficient amount of days of cold, for a consecutive period, during their winter dormancy, or fruit production will suffer. Conversely, a late frost in May can kill blossoms or young fruit. Not too warm, not too cold, but just right!
  4. Pruning: trees that are regularly pruned are much more apt to produce quality fruit. If a tree produces too much fruit in one year it will exhaust its resources and can’t produce the following year.  Thinning out of the fruit every year will solve this problem and be better for overall tree health.  Be fairly ruthless with the thinning, leaving only one fruit per cluster or approximately one fruit to every 40-75 leaves.  Leave fruit evenly spaced on each branch in order for it to mature with good air circulation and light penetration. Knowledgeable pruning is worth studying, related to each type of tree.
  5. Soil conditions: it is very important that your trees have the right balance of reserve food, soil elements, and ground water. And having your soil tested will give you plenty of insight into your garden’s — and trees’ — condition.
  6. Spacing: fruit trees that are planted too close to one another will compete for soil nutrients, air and light. You didn’t mention the size of your orchard, but it may be possible that your trees are planted a bit too close to your house, or garage?

As a reassurance, please know that many gardeners share your concerns, and you are by no means alone! Susan Poizner’s Growing Urban Orchards contains a full palette of concise, well-presented information.  You may also be intrigued by her e-book on growing fruits (available for free download), and, further, you will see, Poizner offers seminars.

The link to her book: https://www.orchardpeople.com/book/

Here are other resources for further study:
1. Health of the tree (including the sun exposition, water, soil, fertilization, pruning)
https://www.torontomastergardeners.ca/gardeningguides/the-organic-fruit-garden-a-toronto-master-gardeners-guide/

https://extension.psu.edu/home-orchards-why-is-there-no-fruit-on-my-tree

Gypsy Month: You also asked whether the Gypsy Moth could be the problem. It very well may be. This is a bad year for this invasive and destructive insect. But if the worms are attacking your trees, they are rather visible with their bright red spots.

The European Gypsy Moth (Lymantria disport) is a non-native defoliating insect that feeds on a variety of tree species found in the Greater Toronto Area (GTA) and throughout North America. They are now firmly established in Toronto and North America, so the complete removal of these insects is no longer a possibility.

Gypsy moth caterpillars defoliate host trees, mostly hardwood species, such as: oak, birch, poplar, willow, maple and others, although they can attack fruit trees. During outbreak years, nearly all broadleaf trees may be completely defoliated, caterpillars appear everywhere, and “frass” (caterpillar droppings) appear to rain from the trees. Adult gypsy moths are only seen in mid-summer when temperatures are above freezing.

Applying sticky bands around trees will stop the caterpillars from travelling up the tree to eat.  These bands can control gypsy moths, tent caterpillars, canker worms and climbing cutworms, depending upon the timing of the application of the bands.

The City of Toronto has a number of excellent web sites detailing the life cycle and how the homeowner can deal with the control of these destructive insects.  I am posting one of these here.

https://www.toronto.ca/services-payments/water-environment/trees/forest-management/threats-to-trees-insects/european-gypsy-moth/

You can find the supplies needed to create the sticky barriers in garden centres and big box stores.

Thank you for helping to maintain our tree canopy.