Last weekend was likely a pleasant and busy one for most gardeners as they cleaned up landscapes damaged by winter’s freezing temperatures. Many plants in home landscapes may appear to be dead at first glance including Blue Plumbagos. Blue Plumbagos rank as one of my favorite perennials. Yes, my Blue Plumbagos looked dead but I know from experience that most plants would likely produce new sprouts near ground level from woody stems not damaged from freezing temperatures.
During the past weekend, I removed the dead branches on each plant (and I have quite a few plants). All the plants had new sprouts already budding out. I’m confident that my landscape will once again be adorned with a plethora of delicate blue flowers.
I love seeing the color blue in the landscape. During the scorching heat of our Gulf Coast summer days, nothing cools us down like the true-blue flowers of Blue Plumbago. Although blue flowers are a rare occurrence in the plant kingdom, they are easy to blend with other colors and go with virtually any color scheme.
The following is a sampling of recent questions asked by home gardeners:
Q: I have followed your advice to hold off any major pruning of freeze-damaged shrubs and perennials? Can I prune them back now?
A: Before answering, I should note that the above question, or variations of the same, was the most asked I answer during the past few weeks. In previous columns, I advised gardeners to wait a while before pruning back freeze-damaged plants. I even followed my own advice as I explained in the opening for this column.
One gardener relayed a conversation she had with her husband as he was preparing to practice major pruning to their home landscape a few days after the last freeze in February.
She said she explained to her husband that it was not time to do such pruning because “Dr. Johnson warned against doing so.” She conveyed to me that her husband replied that “You mean that all the other neighbors that are pruning their landscapes on this beautiful day are wrong and Dr. Johnson is right?” She responded “Yes,” and the pruning mission was put off.
So, yes, it would be far safer for the health and performance of landscape shrubs to delay pruning by a few weeks when a cold snap occurs in February.
Waiting a few weeks or so to give the plants time to seal off damaged tissue and prepare for new growth is worth denying the understandable urge to prune early. Pruning too soon also signals plants to send out tender new growth, which would be even more vulnerable if subsequent cold temperatures occur.
Pruning away the dead portions too soon after a cold snap exposes buds that may still be alive. And another frosty morning could wipe out those survivors. So, I have recommended keeping the shears in the garage and let the dead portions of the plants protect the understory.
The threat of another severe cold snap has considerably lessened. It would be satisfactory to now prune landscape shrubs and perennials that sustained damage from cold weather.
As I was surveying the shrubs at my office in Carbide Park, I noticed that several Esperanza, also known as Yellow Bells and Tecoma Stans, have produced new growth at the base of the plants. If your cold sensitive shrubs have started to put out new growth at the base, go ahead and prune back the old top growth. Be sure to be prepared to cover the new growth with a sheet or blanket as such new growth is particularly sensitive to cold temperatures.
Q: How can I attract beneficial insects to my landscape?
A: The use of beneficial insects to help manage their pest relatives has been a mainstay among gardeners for a very long time. There are several excellent advantages to this method of insect pest control. Utilizing beneficial insects requires a minimum of effort by the gardener and helps reduce the incidence of insect pests with resistance to insecticides.
Gardeners can attract and keep our natural friends in their home landscape and gardens by following a few recommendations, many of which is just good gardening sense that we use anyway. One way to conserve beneficials is by avoiding indiscriminate use of insecticides. While they play an important role in pest control, indiscriminate and improper use of insecticides can also pose a hazard to ourselves and our environment. For more information on how to attract and maintain beneficial insects, visit my website (http://aggie-horticulture.tamu.edu/galveston/) and click on the link entitled “Beneficials in the Gardens.”