Tree Care Diary – May

Flowering Lilac tree


Maintenance May

Time spent in your yard now will help ensure verdant growth in the summer months ahead. We continue with the spring clean up begun in April – see our diary for that month in the link to the right. We outline several simple but key tasks in your garden for the month of May. As ever, timings may differ depending on your state and elevation etc as per the health warning at the end of these tree care suggestions.


Pruning Flowering Trees
– Prune trees that flower in spring after their blooms have ended. This will encourage flowering in subsequent seasons.

Early flowering trees that should be treated this way include forsythia, magnolia, dogwood, lilac and wisteria.
Magnolia Tree flowers

Those that flower in the summer such as crape myrtle should only be pruned in the winter months.


Prepare for a bright green summer –
The Mulching plan we advocated in our Tree Care Diary for March should already be paying dividends by retaining moisture in the soil and reducing weeds. A major benefit will be to reduce the amount of watering your trees need when the weather gets hotter. Take the opportunity to check that the layer of mulch is maintained at around 3 inches deep. Also ensure that mulching material is kept away from the bottom of the tree trunk at grade. This will ensure that moisture-loving diseases such as canker do not take hold. And for that new tree which you planted as part of Arbor Day at the end of April, create a new mulching are as advised in our March diary.

If you have chosen not to mulch, then you will need to:
1. Devise an alternative fertilization and irrigation plan for your tree – an expert can help here; and
2. Avoid using herbicides anywhere near the roots of your tree when trying to remove the weeds that would have been suppressed with a mulch; and
3. Avoid damage to trees when mowing your lawn.


Prepare for stormy weather
– If you’re concerned about damage to your trees from the upcoming storms in your state, there are means to reduce the damage from all but a direct hit by a tornado. Firstly, your trees can be trimmed to reduce their wind resistance. Ideally, this should have been done in the winter but it’s still possible to do now with help from a professional. Secondly, your vulnerable trees can be braced or cabled. Again this must be completed by a trained and certified tree care expert.


Pesticide control
– Depending on the pest inspection you conducted in April (see our Tree Care Diary for April on Pest Inspection), it may be beneficial to apply a tree spray for the specific fungal or insect infestation that you or a qualified professional has identified. The timing of your spraying is crucial so as to avoid killing pollinating insects such as bees.
Bee on blossom
Generally, bees are active during the day, so the early evening will be the best time to spray at this time of year. And instead of automatically reaching for your spray gun consider natural pesticide remedies too. There are plenty of organic alternatives that are less harmful to your garden environment and all who live within it. We’re happy to tell you about them.


Consider calling a tree care professional to:

  • Help with your recognition of tree disease and insects damaging your trees
  • Guide you or carry out a pesticide spraying program
  • Run your spring fertilization program
  • Prune your spring flowering trees.

Call Tree Top Pros for any tree care issue you may have.


Kindly Note:
The accuracy of this calendar and timings shared within it cannot be guaranteed. States in the USA are at different latitudes, longitudes and have varying elevations. This makes the general advice we give hard to fit all states the same. Compounding these differences are the type of tree species that vary between states. Furthermore, each state has its own weather patterns and levels of rainfall. All this calendar can do is broadly summarize best practice care for your trees. We therefore suggest that you consult your local arborist for more specific insights and advice relevant for your particular location.

Tree Care Diary - June Part 1
Tree Care Diary - April