Gardening Patience for Cold-Damaged Plants

Gardening Patience for Cold-Damaged Plants

Our recent cold weather was not only a surprise for many locals but also for many plants that still had plenty of green growth. After a couple of nights of freezing temperatures, even deciduous trees that had not dropped their leaves, look a little ratty.

Since it is just the beginning of December and we are likely to have many more days this winter with cold weather, now is not the time to react to plants that were damaged. There are a few exceptions of plants that you can prune back, but in general patience is the key for the winter garden and cold-damaged plants.

Here are a few guidelines.

Unless planted in very protected spots, annuals like coleus and angelonia were killed by recent cold air. You may remove these plants or cut them back close to the group to make garden areas look neater. You may want to add some new winter annuals to brighten up these spots.

Warm season annuals can be removed from the garden.

Both young and mature citrus trees experienced injury since many plants still had tender growth. Do not prune out any damage at this time. We will wait until next Spring to learn where the growth will resume and then prune as necessary to remove dead branches.

Citrus tree_bolles

The tender growth on a young Meyer lemon was damaged by cold air.

 

 

As expected, the above ground portions of flowering perennials were severely injured by cold air. It is best not to prune these back now since the layer of branches and foliage may help insulate lower branches that could still have some life. If you are not able to tolerate the look of cold-damaged perennials in your garden, consider only pruning half of the plant just to make a neater appearance in the garden. When warm weather returns next year, we may be surprised to see growth resume on lower stems.

Tibouchina_Bolles

Many flowering perennials like Tibouchina will return from the ground next year.

Deciduous trees that would have normally dropped leaves before the cold have full canopies of dead leaves.  Trees will eventually drop these leaves aided by winter winds and rainfall.

Japanese maple _bbolles

This Japanese maple will eventually drop it’s cold-damaged leaves and offer attractive bark and structure in the winter garden.

Plants change with the season

Plants change with the season

As the season changes, plants change as well. This is true in evergreen and deciduous trees and shrubs as well as our lawn grasses.

The cooler night temperatures and the shorter day length of fall result in changes in the physiology of many of our landscape plants and lawn grasses.

It’s common for azaleas to lose a few leaves now. These are the older leaves on the stem near the center of the plant. They turn reddish or yellow and drop from the plant. This is normal from now until spring. However, if the younger leaves, those nearest the tip of the shoot, turn yellow or brown there is cause for concern. Poor drainage, lack of water or alkaline soils may cause this condition.

Yellow leaves may appear on camellias, gardenias, cherry laurel and oleanders. Again, as with azaleas, these are the older leaves on the stem near the center of the plant. It’s normal for these leaves to drop from the plants now until spring. However, do not confuse scale damage on camellias for normal aging of leaves. Scale insects feed on the lower surface of camellia leaves causing them to become splotched with yellow.

Many of the leaves on sycamore trees have changed from green to brown. Although this phenomenon occurs every year, it’s not caused by a change in day length or temperature. This is not a true seasonal change. It’s the result of insects feeding on the leaves. By the time the damage is visible, there is little that can be done to correct the problem. However, the problem will take care of itself since sycamore trees will soon be dropping their leaves.

Lawn grasses also experience some seasonal changes. The growth rate of lawn grasses slows in the fall. Although this slowdown in growth means less mowing is required, it also means that lawns will not be as attractive as they were during spring and summer. Because of this reduced growth rate, grasses cannot produce enough new leaves to replace the leaves that are dying. The end result is a dull, yellow-green lawn.

Normal seasonal color change in centipedegrass lawn from green to reddish purple. Photo by Larry Williams, Okaloosa County Extension

Normal seasonal color change in centipedegrass lawn from green to reddish purple.
Photo by Larry Williams, Okaloosa County Extension

Normal seasonal color change on older 'Little Gem' Magnolia leaves. Photo by Larry Williams, Okaloosa County Extension

Normal seasonal color change on older ‘Little Gem’ Magnolia leaves. Photo by Larry Williams, Okaloosa County Extension

 

Numerous reddish-purple blades throughout the lawn may be visible now as well. Cooler temperatures, injury to the leaf blades from foot traffic, mowing equipment, vehicles, etc, can cause this. It also could be caused by lack of potassium or phosphorus but is more likely the result of cooler temperatures, especially if it did not show up until fall.

New Flowers, Incredible History

New Flowers, Incredible History

diascia basketSince 2005, multiple varieties of Diascia have added to the U.S. fall market of winter flowering plants. Its delicate flowers are far from ordinary though.  In the early part of the last century most British gardening encyclopedias listed just one diascia – Diascia barberae – derived from seed collected by Col. J. H. Bowker and sent by Mrs. Barber to Kew Gardens, England, in 1870. Annual and perennial diascias had, of course, already been discovered and classified by several botanists visiting South Africa much earlier.  The  dainty, little annual, Diascia barberae, is not a very showy flower, but one which will appeal to the true flower lover. The flowers are rosy pink with yellow-green spots in the throat. The flowers are lipped, being related to the Snapdragons, but have two spurs on the lower lips, and are sometimes called twinspur.  It was not until John Kelly was given a plant called Diascia cordata by Edrom Nurseries in 1971 that anything notable happened to diascias again. He took pollen from his Diascia cordata and applied it to one flower of Diascia barberae. Of the nine seeds he obtained, just one was worthy of attention. He named it Diascia ‘Ruby Field’ (not for the color of the flowers, but for a lady who devoted her live to the long-term care of deprived children). Despite the popularity of this new, hardy hybrid, little more happened with diascias for yet another decade.  The boom in the diascia trade began only recently. Today’s diascia offers larger flowers, larger plants with a more open growth habit and colors ranging from scarlet through salmon and coral into pink. They bloom throughout the cooler weather and may behave as a perennial in warmer sites.  But, the uniqueness of their flower structure and ecological role are as fascinating as the flower is beautiful.  diascia flowerThe common name of twinspur refers to the two downwardly pointing spurs found on the back of the flower.  The spurs contain an oil which is collected in the South Africa wild by Rediviva bees.  The female bees have unusually long, hairy forelegs that are used to collect the oil to feed her larvae.  However, the Greek origin of the Diascia name doesn’t refer to the spurs, but rather the two sacs found in the upper part of the corolla.  The flower petals help the bees to rediviva beeorient themselves to the oil glands of the spurs.  While North Florida isn’t home to the Rediviva bee, we can grow Diascia and it is a wonderful opportunity to show the unique connection insects and plants can have.  Look for other specialized flower structures and you will find other animals that fit them perfectly, even within the species found in the Panhandle.

Bold Colors for Your Fall Landscape

I think it’s safe to say fall is officially here. Shouts can be heard from local football stadiums, occasionally a crisp fall breeze will send us looking for a light jacket, and coffee shops are pushing all things pumpkin. Now that we can officially appreciate the cooler fall weather, it may be time to stretch our legs and marvel at the spectacular show of color our landscapes are putting on. Here are a few plants that are showing off this time of year.

Firebush (Hamelia patens) – This charming Florida native will delight everyone with beautiful orange-red flowers throughout most of the year. Hummingbirds and butterflies enjoy the nectar in the flowers. Firebush can reach a height and width of 8 to 12 feet. It is a fast growing plant that will grow well in part to full sun environments. 

Bright orange-red blooms on a firebush. Photo courtesy UF/IFAS.

Bright orange-red blooms on a firebush. Photo courtesy UF/IFAS.

Salvia (Salvia spp.) – Salvias are great plants for bringing butterflies and hummingbirds to your garden and as a bonus, they have no serious pests. With hundreds of annual and perennial species coming in an array of colors and sizes, you can easily find one or more to complement your landscape. Salvias perform best in full sun environments and are considered drought tolerant.

Deep purple blooms on a salvia in the landscape. Photo courtesy Taylor Vandiver.

Deep purple blooms on a salvia in the landscape. Photo courtesy Taylor Vandiver.

Turk’s Cap (Malvaviscus arboreus) – Turk’s cap can add a cheerful pop of color at a time when little else is blooming. This old-fashioned Florida-Friendly shrub like perennial is related to the hibiscus. It’s known for its bright red flowers that always seem ready to open, but never do. Turk’s cap starts blooming in summer and keeps going until through winter, unless hit by a hard frost. It can grow in full sun and reach up to ten feet tall and ten feet wide, so give it room to grow. This easy-care native perennial requires little maintenance once it’s established.

Turk's cap showing off its unique blooms. Photo courtesy Taylor Vandiver

Turk’s cap showing off its unique blooms. Photo courtesy Taylor Vandiver

Coleus (Solenostemon scutellarioides) – When imagining fall color we often don’t consider coleus. However, the vibrant foliage can add interest to any landscape throughout the fall. Coleus is prized for its colorful foliage, which comes in shades of green, yellow, pink, red, and maroon. Coleus varieties can range from one to several feet in height. They can be used in hanging baskets, containers on patios, or in landscape beds. Coleus prefers partial shade  and you can pinch the growing stems of young plants frequently to encourage dense foliage. Keep an eye out for mealybugs on coleus and use insecticidal soap if problems develop

Burnt orange foliage standing out amongst the neutral green of the landscape. Photo courtesy Taylor Vandiver.

Burnt orange foliage standing out amongst the neutral green of the landscape. Photo courtesy Taylor Vandiver.

Fore more information contact your local extension agent. Also you can visit us at  gardeningsolutions.ifas.ufl.edu or edis.ifas.ufl.edu.

 

 

Vegetable Crops for Fall Color

Vegetable Crops for Fall Color

Color can make a landscape.  Color highlights features of the landscape and draws the eye as a focal point itself.  Spring color is dominated by lush new green growth, Summer brings on flowers of all kind, and fall brings the spectacular show of foliage.

[important]A new suggestion: use vegetable crops as fall color![/important]

Fall and winter vegetable crops for the panhandle of Florida bring a different hue of colors that can be utilized in the landscape.  Let’s walk through a few that you may want to start seed for to brighten up your fall garden.

Swiss Chard

Swiss Chard brings several colors to our finger tips.  Reds, Whites, Greens, and Yellows are all available from different varieties of these crops.  Not only do they bring great color to the landscape but they also are sometimes referred to as the “Champagne” of greens.  They can be directly seeded or transplanted and should be planted 6-12 inches apart.

Swiss Chard Varieties. photo credit - Blake Thaxton

Swiss Chard Varieties. photo credit – Blake Thaxton

 Broccoli & Cauliflower

Broccoli brings a blue/green foliage and Cauliflower various colored heads.  Both can bring great color to the landscape and allow for something delicious to eat in the very near future.  Broccoli and Cauliflower transplants should be used for planting.  Broccoli and cauliflower should be given plenty of room with approximately 24 inches between plants.

Broccoli Varieties. photo credit - Blake Thaxton

Broccoli Varieties. photo credit – Blake Thaxton

Cauliflower Varieties. photo credit - Blake Thaxton

Cauliflower Varieties. photo credit – Blake Thaxton

There are many other crops to consider for fall color such as Lettuces, Cabbages, Kale, Etc.  Comment below with other vegetable crops that can be used for fall color.

Gardening in Containers

Gardening in Containers

In a world of limited time and space, container gardens seem to make more and more sense. Poor soil and no place to put plants in the ground are no longer good excuses for not being able to enjoy the simple pleasures of gardening. Container gardening allows the individual to create gardens to fit any situation. Gardening in containers can be just as rewarding as having a full-size garden.

There are a few items to consider when you are planning your container garden. The first is the plants you intend to use. If you are planting more than one plant in the same pot be sure that all your plants meet the same requirements. The requirements you should consider are amount of light, amount of water, climate and fertilizing needs. Some other things you might want to think about when planning your container garden are height, color, and texture. A nice variation of these elements will make your container gardens more attractive and increasingly more interesting to look at.

The next step in container gardening is choosing your container. A good rule of thumb is: “Anything that holds soil and has drainage holes in the bottom may be transformed into a container garden.” It can be a pot you purchased from the local gardening center or an old bathtub you picked up off the side of the road. However, be sure that the size of the container matches the current and potential size of your plant. For vibrant plant growth, the containers must provide adequate space for roots and soil media, allowing the plant to thrive.

Colorful containers bring life to your small spaces.

Colorful containers bring life to your small spaces.

Next on your list is choosing a soil for your container. Container soils need have good aeration and decent drainage, while still being able to retain enough moisture and nutrients for plant growth. When choosing what to use in containers, never use garden soil by itself. When garden soil is added to a container, both drainage and aeration are severely impeded, and the results are plants that grow poorly or not at all.

Container soils are often referred to as soilless or artificial media, because they literally contain no soil. They are commonly composed of various media such as peat moss, perlite, vermiculite, bark and coir fiber (ground coconut hulls) in a variety of mixes. When using soilless media remember t0 moisten it slightly before planting. Fill a tub with the media, add water and lightly fluff the media to dampen it. This will keep the mixture from becoming hydrophobic (unable to take up water) throughout its life in the container. When adding media to your containers, never fill the pot to the top. You should leave about a one-inch space between the top of the soil and rim of the pot. This will make watering the pot easier as it provides a place to “put water” and not have it run over the edge.

When watering your container gardens, the best time to do so is in the morning. Watering in the morning allows the leaves of your plants and soil to dry out, preventing diseases and viruses. Remember that overwatering is the most common reason for fatalities in container gardens. Check your soil by pushing your finger into the media; if the media is moist don’t water it. When it comes to fertilizing your container gardens, fertilize only as needed. Over-fertilization will result in a buildup of salts and may burn the roots of your plants. Try to fertilize your plants during the growing season, and only if needed during the dormant seasons.

The most important objective when container gardening is to be creative. Maybe, try a variety of plants in one container garden. While an nicely put together individual container can be quite impressive, think what might happen if you put several containers together in a group. Also, don’t limit your container gardens to flowers–many vegetables can be grown in a container and actually do quite well. There really is no limit to what can be done in a container!