Tired of Putting Frost Blankets Over Your Tender Plants?

Q. You talked about the freezing temps in the valley. When we had the first freezing temp, I covered what I thought were my most tender plants with freeze cloths. But they were damaged anyhow. If we have another freeze, do I cover them again been though their damaged? It’s a pain covering tender plants!

Wow! This looks great! That means in February my lowest temperature in Las Vegas will be 45°F and my highest temperature is 66°F. The  uppre temperature estimate from those weather people was probably right. But that bottom temperature was wrong. Average temperatures presented by Weatherspark.com. February low temperatures were at or below freezing seven times. Do you smell a tourism conspiracy here?

A.  So, you thought having freeze-tender plants requires no work? Whenever landscaping with plants that do not belong in our climate zone, expect them to “cost” you in time, energy and money. That’s “our agreement” with these plants when we use them.

   Don't trust what you read about low temperatures in Las Vegas. 

We had 3 hard freezes come through the valley in February. Those crop covers or "anti-freeze blankets", only protect tender plants to about 5° F below freezing. If it gets colder than this, they get damaged anyway. The amount of damage depends the condition of the plants, how cold it gets and for how long.

Tropical and even semi tropical plants don't grow here.

            Tropical plants like Moringa, which has become popular Locallybecause of its reported health benefits, won’t handle any freezing temperatures at all. Compare it to Bougainvillea and handle it the same way; cut it back to within a few inches of the soil and let it sucker from its base.I grow it on our farm in the Philippines but I don't have to protect it. If it gets too large and I can't harvest the leaves anymore, I cut it back about 6 to 8 inches off the ground and let it sucker from the base.

Moringa, called malungay in the Philippines, is a tree common to our farm because we use it for a lot of cooking. There are probably about 15 trees that are continuously cut back and suckered again from the base so that the leaves are easy to harvest.Freezing temperatures acts just like a chainsaw and, once established, it will re-sucker again from the base after a hard freeze. Just protect the base of the tree during extremely cold weather.This tree is a weed in the Philippines and we don't have to do much for harvest.

            Semi tropical plants like many citrus show different degrees of damage depending on its age, if it was flowering or has tender fruit, and how it was fertilized the previous season.

Dalandan, or sweet orange, stays green in the hot tropics and is ripe when it's green and easily peels with its thin skin but it will freeze in Las Vegas. The amount of damage depends on how old the tree is, how low the temperature got and for how long. One of our citrus on our farm.We don't have to do much to grow this tree in the Philippines; water, fertilizer and horticultural oil to reduce scale infestations is about all it needs. We don't have to cover it.

            There are 3 things you can do to reduce plant losses prior to freezing temperatures; don’t fertilize after August 1 the previous year if using mineral fertilizers, construct windbreaks around your plants to minimize damage caused from combined low temperatures plus wind, pile mulch or dirt around the trunk of these plants just before freezing temperatures. 

Soil is a pretty good insulator from the cold and wind. If you’re using compost as a fertilizer, then apply it only once in the spring and no more.