Soil & Fertilizer

The Las Vegas Valley has a variety of soil types, including clay, sand and rock-hard caliche. Give your plants an advantage with the use of fertilizer and by amending the soil with additives.

Native desert soil contains a small percentage of organic matter, which is needed to support beneficial microorganisms. Many of the nutrients needed to support plant life are missing. The pH or relative alkalinity of the soil may be high, limiting some nutrients we add through fertilizing.

Soil analysis

If you can, get a soil analysis to help you better outline your yard's soil additive needs. For advice and assistance, contact the University of Nevada Cooperative Extension at (702) 222-3130.

Preparing the soil

Before planting or upgrading your landscape, reduce the soil compaction by rototilling and soak the ground to further soften it. Loose, soft soil allows plant roots to spread easily. While a rototiller is appropriate for large spaces, use a pick-axe for smaller areas and break up at least the top eight inches of soil.

Add organic material to the depth of several inches over the entire site to be landscaped. This is more beneficial than adding amendments to only the area of the planting.

Useful organic materials:

• Sulfur - Adjusts the pH levels of alkaline soil.
• Phosphorous - Promotes root growth.
• Peat moss - Loosens clay soils and provides sandy soils with more body.
• Bone meal - Slowly releases phosphorous and nitrogen for root growth.
• Blood meal - Adds nitrogen to the soil.
• Perlite - Increases aeration and drainage.

Create a mix of one-third organic material to two-thirds native soil. Native plants can survive with less, but these amendments help reduce plant stress during transplant. Organically-rich soils may create overly wet conditions, possibly resulting in root rot or premature plant failure. This is especially true for desert native trees such as Mesquites and Palo Verdes.

Fertilize fruit plants

Peak blooming season is in the spring, and the best time to fertilize fruit trees and grapes is the six weeks before and after they bloom. Fertilize in late winter or early spring for the finest fruit.

Leaf scorching and burning

Leaves usually are stressed for one of two reasons: improper watering or improper fertilization. Since both overwatering and underwatering can damage plant leaves, the best solution is to water deeply and infrequently. This allows oxygen in the soil, washes salts away and encourages deep rooting.

For most trees and shrubs older than three years, water deeply once every seven to 10 days (Run your drip system one to three hours to soak the root zone). Newer plants may need water twice as often until established. Add a layer of surface mulch 2- to 4-inches thick to conserve water between waterings and cool and enrich the soil.

Make sure you have the right fertilizer both for your specific plants and for the time of year. Some fertilizers release much faster in hot weather, increasing the potential for damage. Follow package directions exactly and err on the conservative side. Then, irrigate well to move nutrients to the soil.

Best time to fertilize and aerate your soil

Fertilize in late-September or early-October with a balanced mix of nitrogen, phosphorous and potassium. Fertilizer not only improves turf quality, root growth and color—it also builds cold resistance into your grass. Fertilize once more in November to get your landscape through winter with style.

Aerate grass in September or October as well. Compacted soils are all too common here. Aeration boosts water penetration, which reduces runoff on slopes and helps water and fertilizer nutrients get down to the roots. Aerate again in the spring.