Heat Limits

• Too much sun can wreak havoc on tomato plants.Sun image by KPICKS from Fotolia.com
  
  As the temperature rises, tomato plants can adapt. They actually prefer warmer temperatures. But, once the temperature goes above the 90 degree mark, tomato plants will tend to cease pollinating. The plant is generally done for the season once this happens. It is important to make sure tomato plants have adequate shade once the temperature begins to increase to protect them. Moving plants to shade is suggested if they are in a container, or set up a form of shade for in-ground plants. Tomato plant leaves are a natural shade, so they should be covering the tomatoes.
  
  

Water consumption

• More water is necessary during excessive heat.boy and watering can image by Maxim Pimenov from Fotolia.com
  
  Similar to other living creatures, tomato plants will consume more water during excessive heat. Tomato plants need to be watered at their bases so the leaves and fruit are not splashed with water. Gardeners also have to be careful not to water plants too quickly. The plants need to have time to slowly soak up water at the roots.
  
  

Soil

• Heat can cause soil to crack.italian soil image by apeschi from Fotolia.com
  
  Excessive heat can quickly dry out the soil in which tomato plants grow. It is important to keep the soil soft and not dusty. Once the heat soaks up water, the soil will begin to dry, become dusty and then start to crack.
  
  

Damage

• Tomato plants can be damaged by heat.tomate jaune image by laure paris from Fotolia.com
  
  The damage done to a tomato plant in excessive heat can include wilting stems and leaves that become dried and brittle. Also, the tomatoes themselves can be damaged. Their growth can be halted with excessive heat. Even if they look ripe, tomatoes that have been exposed to intense heat can be red outside and green inside.
  
  

Fruit production

• A fruitful tomato plant requires protection from excessive heat.tomato plant image by Crisps85 from Fotolia.com
  
  The production of fruit relies on tomato plants getting nutrients, water and sunlight. When the temperature rises, unless you have a tomato plant specifically bred for high temperatures, the plant will stop worrying about bearing fruit and try to save itself. Fruit production will be halted. The fruit already on the vines will be compromised.