What Effect Does Temperature Have on Plants?

For most plants, warm weather is essential for seeds to germinate and sprout. Particularly in colder regions, perennial plants need the warmth of spring to break dormancy. Warm temperatures are also necessary for many plants to flower and fruit. Some plants need just a bit of warmth to grow and produce. Others that are native to tropical regions need several consecutive days of heat in the to even break ground for the season. Plants that need the most heat include banana, shampoo ginger, carambola, allamanda, frangipani, lobster claw, mango, papaya, pineapple and many varieties of citrus.

Some plants are not at all tolerant of heat but thrive in cold temperatures. These include holly, camellia, poppy, wintersweet, quince, leatherleaf mahonia, winterhazel, parsnips, asparagus, apricot, raspberry and almond. Some will produce only during winter months, while others need a period of cold to grow properly. Many perennials that seemingly die off during the winter have only gone dormant. They will come back with the warmth of spring.

The home gardener need not be a prisoner of the climate. There are many ways one can grow a plant out of its favorite zone. First, plants that are shielded from wind by a fence or wall can often survive colder winters. Others can be covered, grown in a greenhouse or brought inside. Cold loving seedlings can be placed in the refrigerator or freezer to simulate winter dormancy in warmer areas. Outside, the effects of the heat can be diminished somewhat by planting on a hill in the shelter of some shade. Keep in mind that while plants outside their climate comfort zone can be kept alive, they rarely produce as well. Finally, the home gardener shouldn't rule out any plant until she investigates all of the different varieties. Some traditionally cold loving plants have close cousins that can take the heat.