Plants in the wild thrive without human help because they are adapted to the region in which they grow. The more a plant is adapted to your conditions, the less protection it needs. A truly care-free garden can be made of plants native to your area and to areas with similar climates. There is no need to water the plants during dry spells, protect them from late frosts in the spring, or wrap them up so they survive the winter.
However, many gardeners find this selection of plants too limiting. They want to raise tropical plants in the North, plants that need humid weather in the desert, and fall in love with plants that are not quite cold-hardy in their area.
Even adapted plants need protecting sometimes, such as when seedlings are first set out in the garden, or during extreme weather. Plant protection can be short-term, such as protecting seedlings against a late frost for one night, or long-term climate modification, such as building a shade house for a begonia collection.
Plants need protection against weather that they can’t tolerate without help. Weather factors include:
- Temperatures that are too high or too low for them
- Light levels
- High winds
- Rain and hail
Plants also need protection against diseases, insects, and animals that would like to eat them.
Frequently, one method protects plants from many things at once. For example a row cover over a vegetable bed protects seedlings from the cold when they are first set out, and from birds that like to eat seedlings. Later, the row cover protects against flying insects by keeping them away from the plants. When the summer gets hot enough to stress the plants, the sides of the row cover can be lifted to ventilate the plants, and the top protects them from the hot sun. Greenhouses and cold frames also protect plants from many things at once.