Although plants require a measure of heat to produce food and expedite growth, excessive heat can damage plants. The effect of heat on plants differs across various plant species. Even highly resistant plants such as cosmos, gaillardia, lantana, and lavender could be damaged if exposed to excessive heat waves.
Fruit plants and vegetables are the most easily susceptible. A plant affected by heat waves may not show symptoms immediately. Depending on the plant species, it may take some time before the effect can be spotted.
Effect of Heats On Plants
There are various effects of heat on plants. The intensity of damage varies depending on the nature of the plant. Some plants can withstand extreme heat waves as high as 90°F with leaves still healthy and waving to the breeze.
Some species cannot withstand even 40°F of heat waves, like fruit plants and vegetables. The leaves wilt and collapse as heat rages. Below are some identifiable effects of heat on plants.
Low Yield
Extreme heat affects plants’ metabolism. It resists them from conducting basic metabolic processes needed to grow and flourish. It reduces the ability of the plant to effectively utilise the photosynthetic process to generate its food and trigger growth. This results in low yield and stunted growth.
Susceptible To Pest And Diseases
Studies have shown that heat stress can be very disastrous to the ability of the plant to resist attacks by pests and diseases. When plants absorb extreme waves of heat energy, it deteriorates basic disease-fighting hormones, making them vulnerable to minor and major plant diseases.
Heat tolerant plants can easily weather the problem of heat stress, but disease-resistant hormones will be affected when it approaches extremes.
Wilting And Yellow Leaves
You can easily spot this effect when your plant is suffering from excessive heat. Heat waves limit the ability of the plant to manufacture its food through the process of photosynthesis. When this happens, the sleeves wilt and turn yellowish because it does not have access to enough nutrients and food.
Leaf Drop Of Tree Plants
Leaf drop is always peculiar to tree plants when under intense heat. Due to their height, they are always easy casualties of excessive heat. The branches will spread out stripped bare without leaves, and the ground below the trees is always covered with the dropping leaves. It is an effect of heat.
Death
Extreme heat kills and damages plants as it makes it impossible to access essential plant nutrients necessary for survival. As the heat rages, plants lose water on the soil, leaves, and other parts of the plant, exposing them to drought conditions. This finally results in death.
How Plants Cope With Heat
Plant deploy specific adaptive measures to cope with heat and drought conditions. However, the coping strategy varies across species. There are plenty that can tolerate heat and drought conditions. Some plants are less tolerant to heat and drought conditions as well. Below are some adaptive measures that some plants use to adapt to heat and drought conditions.
Ability To Retain Water
Water is an essential compound necessary for plant survival. It is a perfect additive that can douse the effects of extreme heat waves on plants. A plant retaining water for longer periods is more likely to survive heat and drought conditions. Examples are succulent plants such as Hens and Chicks, Cactus, Century Plant, and Aloe Vera. They store water either in the leaves or stems to resist the effect of heat and drought conditions.
Structure Of Plant
The structure of the plant’s shoot and root components determine the plant’s ability to survive heat conditions. Plants with thin-like leaves with few inches of width are more likely to survive excessive heat waves. A thin plant provides less surface area to absorb heat waves than plants with a large surface area.
Deep Roots
Plants with deep roots are more likely to survive heat waves. Deep, strong, and well-spread roots can track nutrients and store more water which may sustain plants’ life in extreme heat conditions. Pumpkin, tomatoes, and winter squash are some of the deep-rooted plants with the capacity to withstand high and intense heat waves.
Hormones Stimulation
Plants are living things capable of responding to specific stress conditions, including heat waves. Steroid hormones are a special type of plant hormone which aids resistance to extreme heat waves. During extremely hot and drought conditions, steroid hormones are stimulated as a biological defense mechanism to enable the plant to survive.
However, steroid hormones only support minimal and moderate resistance to heat. Scorching temperatures force your plant to wilt and die off.
How To Protect Plants From Heat
Heat can neutralize your long-term effort to grow and raise plants for ornamental, market, food, or other purposes. There are limits to plants’ capacity to cope and resist heat; hence it is essential to protect your plants from heat. Below are measures you can take to protect them from heat.
1. Use Shades
Constructing shades or getting ready-made ones for your plant is a reliable method to help keep them off scorching heat waves. The shades deflect and absorb heat waves, reducing their impact on plants. If the plants are moveable such as potted plants, you can simply move them to areas with less impact and heat waves.
Taller trees with spread leaves and branches can serve as shades for your potted plants. Take outdoor potted plants inside when heat waves hit hard. If the plants are not moveable, construct a shade for them. You can move other plants to your constructed shade.
2. Timely Planting
Timely planting is another critical aspect of preserving plants from heat. Heat waves do not preclude cultivating new plants in your garden. If you are timely with the planting, the plant will likely survive heat waves.
Summer heats are unfriendly to plants, but if you must plant, monitor periodic breaks of the scorching sun and plant your seedling. With good care and monitoring, it will be secured despite the heat. Don’t plant a seedling during midday under a scorching sun.
3. Watering
Water is an indispensable element for animal and plant life. Every plant needs water. Some plants are annual and perennial. They crossed the winter and hot summer suns before yielding fruits. Your plant can survive extreme summer heat adequately watered. Water douses the effects of heat, giving the plant a breathing space as heat stress mounts.
4. Use Sealed Pots
Your plants need a measured supply of water to survive. Although water is necessary for the plant’s survival, you should ensure optimal applications as excess moisture may lead to root rot. Creating holes in your potted plants is always advisable to ensure proper dehydration when watered.
However, an exception to the rule is necessary during hot seasons of extreme heat. Potted plants with holes in the pot suffer most in the summer heat. The plant loses water quickly during the period. Patch up the holes during summer to enable the plant to retain more water and weather extreme heat waves.
5. Companion Planting
Companion planting is another novel method to protect your plant from heat. Although companion methods have been deployed to keep pests and diseases away from plants, it is also a veritable tool for plant preservation. Cultivate tall heat-tolerant trees with a good spread of branches and leaves. Grow your desired plants near these heat-tolerant trees. The combination can protect your plant from heat waves.
6. Always Use Heat-resistant Plants
Heat resistance can reduce the stress of serving as day and night stewards for your plants in hot climates. They can withstand high temperatures with minimal attention. Always go for a heat-resistant plant, especially if the climatic temperatures are not favorable.
Note: Using a heat-resistant plant does not preclude taking some measures to protect your plants against heat. It only reduces the rigor of frequent monitoring compared to less resistant plants.
7. Nurture Wilting And Dying Plants
Heat can kill plants, but it takes a process for the plant to die after the damaging effect of heat waves. First, you will observe fatigued and wilting leaves. Some leaves may turn yellowish. Don’t abandon the plant. Keep nurturing by supplying needed nutrients. You can use mulching, compost manure, and watering to resuscitate a plant dying from heat waves.
When Is It Too Hot For Plants?
When temperature crosses the 9°F mark, it is a wild and hostile climatic condition for plants. However, the mark may vary across different plant species and heat tolerance.
How Often Can You Water Plants In Hot Weather?
You should water your plants at least three times a week when the weather is too hot. Slight schedule changes may not be disastrous when handling heat-tolerant plants.
Can You Plant in a Scorching Summer Sun?
You can plant in the summer irrespective of the state or the temperature. But you must follow up the plant with appropriate care and nurturing.