Deciduous Trees –
If June was about staying ahead of growth, July is about survival — this heat wave has pushed us well beyond typical Northeast Florida summer stress, and deciduous trees are feeling it. We're sitting at highs near 97–98°F this week, with little rain to soften the blow until the weekend pattern shifts. This is the point in the season where the priority isn't refinement, it's keeping your trees alive to refine later.
First, ease off aggressive pruning and defoliation work until this heat wave breaks. A tree already fighting to keep its leaves hydrated doesn't have the reserves to recover well from a hard cutback right now. If you've got shoots that need attention, light maintenance trims are fine, but save the harder structural pruning for when temperatures come back down closer to normal.
Shade cloth should already be up if you have one, but if you're seeing scorch, pale or bleached-looking leaves, or branch tips going crispy, it's worth bumping up to a higher percentage shade cloth, if you have it, or moving vulnerable trees to a spot with afternoon shade from a structure or larger tree. Maples and other thin-leafed deciduous species will show stress first — keep a closer eye on those than on something like a Quince or Elm.
Watering technique matters more than watering volume right now. Water deeply, early morning before the heat sets in, and again in the evening once the sun is low. Avoid watering during peak afternoon heat — the water evaporates too fast to do much good and can actually stress roots further with a rapid temperature swing in the pot. Misting the foliage and the area around your benches (not full watering, just a light mist) in the early afternoon can help knock down ambient heat around the tree without oversaturating the soil.
Hold off on fertilizing altogether during the worst of this heat wave. A stressed tree isn't in growth mode, and pushing fertilizer — even a mild one — asks the tree to do more than it can handle right now. Once temperatures moderate and afternoon rain becomes more regular again, you can resume your normal schedule.
Speaking of that incoming rain — forecasts show a shift toward frequent afternoon storms starting this weekend, a 75% chance of rain both days. That's a good thing for hydration, but after a stretch this dry and this hot, be ready for a fast swing into fungal risk once the humidity and moisture come back. Keep an eye on trees in organic soil especially, and don't let water sit stagnant in saucers or trays.
Last thing — check your wire more often than usual this month, not less. Heat stress can mask itself as a wilting or drooping branch that actually turns out to be a wire starting to bite. When in doubt, pull it and rewire once the tree has recovered.
Conifers and Broadleaf Evergreen Trees –
This heat wave changes the calculus a bit for conifers this month. JBP owners in the middle of decandling: keep going per your normal timeline, but watch water needs closely — a freshly decandled tree has less foliage to regulate its own temperature, and 97°F+ heat hits those trees harder than usual. Hold fertilizer until secondary candles harden off, as usual.
For everything else, this is a month to prioritize survival over development. Junipers and pines generally handle this heat well and can stay in full sun, but keep an eye on broadleaf evergreens — Boxwood, Holly, and similar species will appreciate afternoon shade if they're not already getting it. If you haven't put up shade cloth yet, do it now rather than waiting.
Wire checks remain critical — growth doesn't slow down just because it's brutally hot, and cambium thickening waits for no one. Check anything wired this spring at least weekly.
Watering: deep, early morning and evening, avoiding the peak heat hours. With the shift toward regular afternoon storms starting this weekend, watch closely for fungal issues once humidity climbs back up after this dry stretch — Cleary's or a propaconazole-based fungicide are still the best preventive options for conifers, and Daconil remains a reliable go-to for foliar spray if you spot early signs of trouble.
Tropical Trees –
Tropicals are the one group actually thriving in this heat wave — but with the extreme highs we're seeing this week, "thriving" still requires some management. Growth remains vigorous, and the species that needed to wait until July for repotting (Black Olive, Ixora, and similar heat-loving natives) are now fair game. Since we're doing repots and styling at this month's meeting, this is a great window for those particular trees — just keep in mind that with highs pushing 97–98°F, aftercare matters more than usual. A freshly repotted tree has a compromised root system and less capacity to keep up with this level of heat stress, so plan on extra shade and more frequent misting for a week or two post-repot rather than full sun exposure right away.
Fertilizing should continue at full strength for established trees. Freshly repotted trees are the exception — hold off until new root growth is confirmed, typically 3–4 weeks out, so you're not asking a stressed root system to process nutrients it can't yet use.
Watering demands are at their peak, and daily watering may not even be enough for trees in small pots or full sun during this stretch. Keep watching for wilting even when soil is moist — that's a root system that can't keep pace with transpiration, and it means it's time to get that tree out of direct sun, not add more water.
Pest pressure remains high in this heat and humidity. Keep up with Imidacloprid treatments on your regular 6-8 week cycle, and continue checking weekly for scale, spider mites, and those cottony Planthopper Nymphs — easy to treat, but they spread fast if ignored. With the shift toward regular afternoon storms starting this weekend, stay ahead of fungal risk too: water early so foliage dries out well before evening humidity rolls back in.
Miscellaneous – Heat & Managing the Health of your Trees
With this heat wave, one simple message applies across the board: check your trees. Often. Collecting and other seasonal projects can wait — right now, the priority is keeping what you have alive and healthy.
Even a little wind on a day like this can push a tree from "fine" to "desperate" fast, pulling moisture out of the soil and foliage quicker than usual. A tree that looked healthy at 8am can be wilting hard by 2pm.
If you started air layers in May or did any tropical grafts recently, this is a critical time to stay on top of them. Both have zero margin for error in this heat — check moisture daily, and don't let air layer wrapping (moist sphagnum) dry out even once. Also double check what you used: clear or black plastic traps heat and can cook developing roots, so tin foil is the better choice, as it reflects sunlight away instead of holding onto it.
Rootbound trees deserve extra attention too. Less soil volume means less water capacity, and a tree that used to go a full day between waterings might now need checking twice. If a repot got delayed, don't assume your normal watering schedule still applies — check the soil directly, not the calendar.
Bottom line: this isn't the month to be hands-off. A few extra minutes walking the bench each day will save a lot of heartache later.
