NMSU branding

New Mexico State University

New Mexico State University

News Center

Time for Gardeners to Give Soil a Boost

LAS CRUCES -- Gardeners, who are preparing to harvest their last crop before the first frost, should also start cleaning vines and weeds and revitalize hard and worn-out soil, said a horticulture specialist with New Mexico State University.

"Fall is the best time to think about next year's garden," said George Dickerson with NMSU's Cooperative Extension Service. "That means beefing up the soil with some extra organic matter before winter sets in."

The best way to do this is by applying livestock manure or planting a green manure crop, he said. Many areas of New Mexico have an abundance of cow manure available from the dairy industry. Gardeners can haul a pickup full of manure for a small loading fee.

Cow manure should be applied after frost at a rate of 50 to 100 pounds per 100 square feet of garden and incorporated with a garden fork or rototiller to a depth of 6-8 inches, Dickerson said. Chicken manure should be applied at half the rate.

"Livestock manure has been used on cropland by farmers since man first began tilling the soil," Dickerson said. "However, manure sometimes contains weed seed."

Properly prepared compost will heat up and kill weed seed, he said. Use manure, leaves and crop residue for composting in the fall. Then, save compost and apply it to the spring garden.

A green manure crop, grown specifically as a source of organic matter, is an excellent way to enrich the soil, he said. The most popular green manure crops are winter rye, wheat, oats or barley planted in the fall and turned under in the spring.

"My favorite green manure crop is winter rye because it produces so much vegetative matter," Dickerson said. "Winter rye can be bought from local feed stores and scattered liberally around tomatoes, squash and other crops, hoed in, and watered during late summer."

When vegetables are pulled up after a frost, a green carpet of rye is left, he said. A little manure or nitrogen fertilizer in the fall and the following spring helps the growth.

"The winter rye can be mixed into the soil with a rototiller about a month before planting vegetables," Dickerson said. "It's a good idea to incorporate extra nitrogen fertilizer at the time to help microorganisms in the soil breakdown all the plant material."