For those people who have a difficult time growing anything in a garden or landscape, just remember most places will support some type of plant growth. However, it isn’t always true that every plant will grow in your landscape or garden. Plants have environmental requirements to grow healthy in a particle location.
Temperature is one of the most important aspects of any environment growing a specific plant. When purchasing plants, temperature requirement for success of that plant should be considered first, especially if the plant is being ordered from a mail order catalog. Plants must be chosen for their ability to survive in the environment we have in our location.
The climate zone in which we live is one of the most important factors to determine what plants will grow in the landscape. The U.S. Department of Agriculture defines these zones and gives the average annual minimum temperature within the region. The average lowest temperature for Comanche County is minus ten degrees to zero degrees, which places us in Zone 7. In seed and nursery catalogs a hardiness zone next to the name of a plant indicates its hardiness to cold.
Oklahoma has a widely varying weather condition. The southern half of the state has a higher summer temperature range than the northern half. The western half of the state has a lower rainfall than the eastern half. Lawton has a lower rainfall range than most of the state because of the weather patterns going around us.
Keep in mind that conditions can vary widely even within the same landscape. Plants in shelter locations may survive extreme freezes, while plants exposed to too rapid warming of early morning sunlight in cold weather may not. In southwest Oklahoma wind can be a big factor in growing conditions by causing hot zones or freezing zones or just damage to plants from blowing to hard.
As most gardeners know there are four seasons. Each season has it own do and don’ts.
Spring is the season for gardening. It is the time when nurseries and box stores have their biggest selection of plant material. It is a good time for planting because the temperatures are low enough to start plant growth. Also, spring gives the plant time to establish a root system before top growth is needed. If the plant is grown for flowers or vegetables, they are able to produce their best at this time.
Summer is a time that is more challenging to growers because of our extreme temperatures (over 100 degrees). In most cases when temperatures get over 90 degrees most plants just shut down growth and go dormant. Many trees and some shrubs will actually drop leaves to stop respiration.
Fall returns great gardening condition. Temperatures will drop gradually and rainfall will pick up. It is a great time for carrying over the vegetable garden or to plant some new vegetable. Fall is a great time for planting new trees and shrubs because this give the plants a chance to grow new roots without growing leaves or fruit.
Winter is a time that most plants go dormant. That doesn’t mean that they aren’t growing. It is a time when they grow new roots, set flowers and leaf buds for next springs. Because most trees are dormant this is a good time to prune.
When purchasing plants, gardeners will encounter two terms relating to temperature: hardy and hardened.
Hardy refers to a temperature at which a gardener could reasonably expect a plant to survive. This is the lowest temperature at which a plant, when properly condition, could be expected to survive.
Hardened is when a plant is gradually conditioned to colder temperatures (extreme heat). It is far less damaging to a plant that is “hardened” or exposed over a period of weeks to lower temperatures (extreme heat) than suddenly placing plants out to these extreme temperatures.
Jim Coe lives in Lawton and writes a weekly gardening column.