Protect your plants from
FROST, FREEZING
TEMPERATURES


January 21, 2011

by Donna Sahualla, Victoria County Master Gardener

edited by Charla Borchers Leon,
Victoria County Master Gardener
Gardeners' Dirt

VICTORIA COUNTY
MASTER GARDENER ASSOCIATION
PHOTOS BY DONNA SAHUALLA/VICTORIA COUNTY MASTER GARDENER
LEFT: Master Gardener Donna Sahualla's garden is ready for the cold weather with this structure built over it. It's ready to cover with plastic. Note the slant to the top so the rain will run off.
RIGHT: This small garden space in Donna Sahualla's yard is covered and ready for cold weather. It's designed to easily roll back and uncover on sunny days, and it works great for citrus, too.
One of the reasons I love living in South Texas is the mild winters. We do occasionally experience some cold nights and days that can be challenging when caring for plants.

Gardeners are resourceful when it comes to tending to their plants, so a little cold isn't going to stop me from gardening.

My first suggestion is if you are planting something new in a flower bed, even in the August heat, be mindful of the location of the plant itself. In other words, don't plant a tropical plant on the north side of your home where you will have to tend to it in 30-degree temperatures. Tuck it in a southern corner exposure of your home.

Gardeners should keep an eye on the weather forecast and be prepared to protect our much loved plants and gardens.

Following are some steps we can take when the temperatures are predicted to drop below the freezing mark:

Water - Watering plants before a freeze can help protect plants. A well-watered soil will absorb more solar radiation than dry soil and will re-radiate heat during the night. Gardeners should remember, though, that long term exposure to overly moist soil can damage some plants.

A fine water mist continually sprayed into the plant's canopy starting before the freeze sets in until ice starts melting will also keep most plants from major freeze damage. Heavy ice, though, may damage small twigs and branches.

Mulch - Think of it as "tucking them in for the night." Mulching gives your plants a "blanket." Together with moist soil this helps protect their roots. I find it beneficial to let Mother Nature do my fall mulching. When the leaves start falling, I rake the leaves from the yard and leave the ones in the flower beds to help protect my plants from the cold weather. It's a dual purpose for my flower beds: decomposing leaves enrich the soil and I get cold protection.

Dried grass clippings or hay also makes good insulation and plant protection.

Provide Cover - Many shrubs, trees and winter annuals tolerate cold, but cover your tender plants and flowering plants. Covering tender plants and shrubs with a blanket or cloth will help protect them through a cold winter night.

Creating a mini-greenhouse out of a few sticks of wood and plastic is a great way for a small garden area. Insert a light bulb under the plastic (set it to prevent a fire hazard) or add Christmas lights to add heat.

For small or young plants, cut the top off a 3-liter soda bottle to create a plastic dome with the base placing it over the plant and sinking the edges into the soil.

Move - The plant that is. Moving potted plants to a more protected area of your yard or even the garage will keep them out of the freezing weather.

My husband dreads this time of year, as my plants turn his garage/workshop into an indoor garden. As soon as the temperatures rise, I move the plants back out to get some of the daytime sunshine that they so desperately need.

Sometimes even just relocating the pot close to a protected area of a patio or near the house will provide enough protection to ride out the cold weather.

If you move plants into your home, remember to be cautious because the drastic change from outdoors to our heated homes can be fatal to some plants.

Should your plants experience a freeze, I recommend removing the soggy, damaged parts on soft-stemmed plants such as impatiens. However, do not rush out to prune freshly frozen woody plants such as hibiscus.

Leave the freeze-damaged wood until it starts to resprout below it in the spring and you'll know then where to prune.

HARDY CITRUS

So many people ask, "When do I need to protect my citrus trees?" It depends on the citrus type, tree age, variety, rootstock, how long of a freeze and time of the winter or tree cold acclimation.

Thankfully, we typically only experience one or two nights of freezing temperatures. If uncovered and you follow some of the steps above though, generally, satsumas are fairly safe until 25 degrees, maybe 22 degrees; oranges down to 28-30 degrees; and grapefruits possibly mid to upper 20s.

See accompanying chart for citrus hardiness.

While protecting our plants seems like a lot of work, it is merely a small price we pay for the beauty and love of gardening. I'll take our occasional freezing weather any day over the brutal cold many of our Northern friends experience over a long winter.

After all, with all the care provided to my plants over the winter, they will be thriving in the spring.
Tips to protect frost-sensitive trees/plants
Water the soil before a freeze
Provide water mist throughout the freeze time
Mulch with insulating leaves, hay, etc.
Cover with blankets, cloths or plastic
Add supplemental heat with lights
Move plants inside garage

Cold Hardiness of Citrus
Citrus varieties vary with cold hardiness, and are
listed below from the most hardy to least cold hardy.
Kumquats
Satsuma
Sweet Oranges
Navel Oranges
Mandarin
Grapefruit
Tangerines
Tangelo
Lemons
Limes

Lunch and Learn with the Masters Monday
Pattie Dodson Health Center, 2805 N. Navarro St.
Free to the public
Noon to 1 p.m.
Bring your lunch and drink
Pruning Shrubs and Trees - Presented by Victoria County Master Gardener Charlie Neumeyer
The Gardeners' Dirt is written by members of the Victoria County Master Gardener Association, an educational outreach of Texas AgriLife Extension - Victoria County. Mail your questions in care of the Advocate, P.O. Box 1518, Victoria, TX 77901; or vcmga@vicad.com, or comment on this column at www.VictoriaAdvocate.com.