Painting a tree trunk white, watering a plant surrounded by mulch, and shade cloth over a large area of raised bed veggie gardens.

Summer Heatwave Tips To Help Protect Your Plants

July 2023 was the hottest month on record, with Arizona's average temperature at 102.7° degrees Fahrenheit—with an average high of 114.7° F and an average low of 90.8° F.

Ongoing, summer heatwaves are difficult on people, wildlife and plants. To help relieve some of the stress your plants are under, here are some key gardening tips from our Master Gardener, Jack.

1. Fertilizing

Hold off on fertilizing until temperatures have dropped below 90° F. Fertilizing in temperatures above 90° F will push new growth which will not have a chance to harden off before getting burned by our intense sun.


SUPERthrive, Boomerang, Kelp Help, Seaweed Extract, and Fish Emulsion with Kelp.

2. Vital Nutrients

While we don’t recommend fertilizing plants during our excessive heat, heat-stressed plants can benefit from diluted vitamin and mineral supplements, such as SUPERthrive®, Fox Farm’s Bush Doctor® Boomerang®, or any of our kelp/seaweed supplements.

Here’s how they can benefit heat-stressed plants:

  • Macro and micronutrients will help heat-stressed plants recover just a little quicker
  • Macro and micronutrients also provide plants with a higher resistance to future stress
  • Accelerated chlorophyll production and photosynthesis makes plants stronger
  • Tip for kelp/seaweed products: A feeding of diluted kelp/seaweed extract applied directly to the leaves (foliar) in the late evening can work exponentially faster than applying it as a soil/root drench

SUPERthrive® - The Essential Vitamin Solution: From stressed plants to producing abundant yields, their unique, non-toxic vitamin solution encourages the natural building blocks a plants makes for when under the best conditions, fortifying growth from the inside out. SUPERthrive® is natural and non-toxic, improves plant vigor, revives stressed plants, reduces transplant shock, and is designed for all plant types and stages of growth.

Fox Farm’s Bush Doctor® Boomerang®: This 2-0.2-0.3 comeback forumla lends a hand when the stresses of temperature fluctuations, unintentional neglect, and mineral salt build up knock your beauties down for the count.  The soil microbes in Boomerang® help support the root zone. Boomerang® can also be used as a vegetative supplement.  It contains solubilized nutrition that is immediately available to plants. 

E.B. Stone Organics Fish Emulsion with Kelp: This all natural plant food helps plants grow, flower, fruit and stay deep green. Registered cdfa organic input material.

Grow More Seaweed Extract: Benefits from this liquefied natural kelp include improved root development, more vigorous growth, increased resistance to environmental stress and reduced frost damage.

Pacific Northwest Organics® Kelp Help: This all-purpose liquid is made from Pacific Northwest bull kelp that stimulates microbial activity to improve: germination, growth, yields, product quality, reproduction, flavor, color, and many other desirable attributes. Registered cdfa organic input material.


A large Palm tree and Petunias being watered by a drip irrigation system.3. Watering

Increase your watering schedule. While its important to provide your plants with additional water, be careful not to overwater your plants or create an environment for your plants and trees to develop root-rot.


Heat Stressed Plant with Dead Branches4. Pruning

Hold off on pruning—even dead branches and leaves. Dead branches and leaves can acutally help provide supplemental shade for the rest of the plant or tree during a heatwave.


A wavy succulent and white rock border in landscape5. Reflected Heat

Pull rocks and gravel away from the base/dripline of trees to reduce reflected heat being directed at the tree.


GardenStraw Premium Mulch in garden with flrowers nearby being watered.6. Mulch!

A thick layer of mulch at the base/dripline of plants/trees will help keep water from evaporating quickly. It will also help to keep the root zone much cooler. Note: keep the mulch from directly touching the trunk.


Shade triangles in garden landscape.7. Shade is the Key!

This may be the most important thing you can do to help your plants. Even with extra water, plants and trees will greatly benefit from supplemental shade to keep their leaves from burning and their stems/trunks from sunscald. Shade cloth, temporary shade sails, and specially formulated tree-trunk paint can help give your plants some relief.

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The above tips can help ease some of the stress your plants are under and provide them with some relief from this unprecedented heat!

At SummerWinds, We Guarantee Success!