Get answers to some of the most common
questions about problems with plants.
A plant's leaves provide the first and most obvious signs that something is wrong with your plants. Here are some tips to help interpret what your plants are trying to tell you:
Small leaves that are dull or bluish tell you plants are struggling for water. This is especially true in lawns. If your lantanas struggle to bloom, they're signaling for more water.
Wilted foliage usually means the plant is short of water, but that is not always the case. Roots growing in soil that is too wet can also cause wilting. Plants stressed from over watering often suffer from poor drainage. Dig down and find out if that is the problem, then drill holes to create drainage through the rooted area if needed. Over fertilizing or a misused herbicide will cause the same problem.
Leaves with brown and dead edges suggest excess salts in the soil, due to poor drainage or compacted soil, which is very common in our valley.
Dead leaves suggest the plant was stressed for water on a hot, dry, windy day. Dead spots on top of leaf centers, especially the exposed leaves, suggest sun burning. This happens when the plant is hot and stressed for moisture, even if just for a few minutes.
Drying and falling leaves on the inside of evergreens indicate they are aging and giving up nitrogen to the younger leaves. You'll see this on olives, oleanders, pines and most evergreen bushes. It also indicates the leaves are not getting enough sunlight, or the plant suffered through a dry spell or shock after transplanting. As trees age, leaves do drop more.
Desert trees and shrubs, such as Palo Verde and Ocotillo, naturally drop their leaves to save water in extreme heat. If the stress worsens, expect overall twig and branch decay.
Your plant is struggling for nitrogen if the older leaves from the bottom up are generally yellow. The rest of the plant is often light green. Plants absorb nitrogen in the form of ammonium or nitrate, but these nutrients readily leach away. Use a fertilizer containing nitrogen, then irrigate to move the nutrients into the root zones. Iron deficiency is a major problem.
Yellowing occurs between the veins of young leaves, and veins become a pronounced green. Alkaline soil strongly affects the uptake of iron. Use chelated iron as it is readily available. If you have a severe problem, use Iron 138, a chelated iron sold as Kerex. Chelates are organic compounds that protect the iron until plants use it.
Got a question about planting native species in the desert? Are you wondering if your HOA approves of certain plants? Curious about the best time of year to prune? The Gardens at the Springs Preserve offers expert horticultural advice on plants and problems, utilizing master gardeners as volunteer Gardens docents to answer questions such as these about desert plants, soils and how outdoor elements affect gardening.
The aim of the master gardeners is to educate people in the proper and successful methods of home gardening. All of the gardens docents know about desert horticulture; some are experts in the areas of cacti or palms or vegetables.
Visit the Gardens at 333 S. Valley View Blvd. or check out the "Ask the Gardener" Web board on the SpringsPreserve.org website. Garden docents will be available at the Springs Preserve on Saturdays from 9 a.m. to 1 p.m.
Your landscape has different needs during each season. To keep your yard healthy year round, visit the Seasonal Tips section for advice on common plant problems related to each season.
Copyright © 2012 Southern Nevada Water Authority