Warm-weather planting looms in Oklahoma
We are getting very close to planting season for most of the warm-weather crops.
Our last average freeze date is about April 7 — Saturday
— in central Oklahoma. That means some years the last freeze is earlier, and some years it's later.
A few years ago, we actually had a freeze on May 3 in Oklahoma City. We have flirted with freezes three nights this week, depending on your specific location.
Most metro-area nurserymen suggest waiting to plant the tender or warm-season annuals until mid-April and the really hotblooded crops like periwinkle, sweet potato vines and caladiums until May 1 or after when night temperatures are consistently above 45 degrees.
Ardmore and southern Oklahoma are usually about a week earlier to warm up, while Enid, Ponca City and Bartlesville are about a week later than Oklahoma City.
You can safely plant trees, shrubs and perennials now as they are more tolerant of a light frost or freeze. It would be wise to wait another week on tomatoes, peppers, eggplant, penta, geraniums, marigolds and other warm-season annuals.
We have had some gorgeous spring days mixed in with our last cool days. The beautiful days really make us want to plant. If you can’t wait any longer and want to get your tomatoes or other crops planted before the neighbors, please be prepared to cover them with row cover, hot kaps, boxes, milk bottles or other protection if we do get another cold snap that flirts with freezing.
When planting your crops, it pays big dividends to spend a little extra time to prepare your soil as the soil is the home for your plants and the foundation of gardening success.
If you have been adding organic matter for years, you likely have established a good loamy soil with good air movement and good water penetration and drainage. In these good, well developed soils you can literally clear any weeds and start planting.
If you have clay or tight soils, you should add organic matter like sphagnum peat, fine composted bark or aged compost based on manure, cottonseed hulls or alfalfa. This organic matter will help lower the pH of our normally high alkaline soils and will improve drainage and allow more air circulation to help support healthy roots.
If you have sandy soil, adding organic matter will help moderate the air movement and will retain more moisture in the root zone while lowering the pH levels to a slightly acidic level where more nutrition is available to most plants.
We are at the very end of the time where you can reduce summer weeds like crab grass in your lawn through the use of pre-emergent herbicides. Remember that pre-emergent herbicides only work if they are applied before the crab grass or other weed seeds germinate. Once the weeds have sprouted we have to switch from pre-emergent herbicides to post-emergent herbicides to get any control.
If you want pre-emergent control you need to apply at once as a weed and feed type product that fertilizes as you kill the weed seeds or as a granular herbicide you spread or a liquid weedkiller you can spray on your lawn.
Our state is in bloom as spring marches forward. We are enjoying the last of the tulip bulbs and the first of the iris in flower. We are seeing the last of the yellow forsythia and the first of the enchanting purple wisteria. We are seeing the last of the fruit tree flowers and the peak flowering of our state tree, the many gorgeous varieties of redbud.
Please take time to enjoy your yard, your neighborhood and your city parks, as well as fun visits to your local nurseries and garden centers.
Rodd Moesel serves as President of Oklahoma Farm Bureau and was inducted into the Oklahoma Agriculture Hall of Fame. Email garden and landscape questions to rmoesel@americanplant.com.