Poinsettias

Poinsettias

A Short History

The poinsettia (Euphorbia pulcherrima) is a plant synonymous with the holiday season. Growing in deciduous forests along the Pacific coasts of southern Mexico it becomes a woody shrub reaching 10-15 feet tall. In 1825 the ambassador to Mexico Joel Poinsett was taken by the red blooms and brought it home to the United States. He propagated and gifted the plant to friends and a few public gardens. Before long the nursery industry took notice and the plant was on its way to becoming the potted plants we see in stores. Today, an extensive breeding program has created a multitude of colors and leaf patterns available to consumers for the holiday season.

Poinsettias for sale
Poinsettias for sale IFAS Photo: Josh Criss

The Plant

Poinsettia is a member of Euphorbiaceae commonly referred to as the Spurge family. The primary feature of this family is a milky sap or latex produced in the stem tissue. Some may be allergic to the latex, but to most it is at worst a mild irritant. This irritation conjoins a reputation of toxicity which may give some pause toward purchasing one. While a very mild toxicity does exist, you would need to consume very large amounts of the leaves to experience negative effects. That said, it is always best to dissuade consumption by pets and children with this and any other house plants.  The flowers of this plant are somewhat unremarkable and appear in the middle of several red leaf structures. These leaves are actually bracts and are protective structures for the flower. As a tropical plant, frosts and freezes have a detrimental consequence for this plant, but in areas where there is little or no risk of cold it may be used in your landscape after the holidays. In these scenarios, it will grow much as in its native habitat into a shrub.   

Mature poinsettia as a shrub in the landscape
A mature poinsettia planted outside of a home. IFAS photo

Care

When kept inside, keep the temperature around 65F at night and 80F during the day. They need full sun and water only when the soil is dry. It is good practice to remove any water left in pot saucers as this plant performs poorly with wet feet. All-purpose fertilizers should used except while this plant is in bloom. When blooming the plant does not require fertilization. Placed outdoors in a protect area once freeze risk has passed. Keep in mind that the bracts are photosensitive. Around October, theses plants will need 14 hours of complete darkness daily to turn their customary red by Christmas. Keep them covered and completely blacked out as even porch lights will delay color change.      

Poinsettias are a beautiful plant and certainly worth your efforts this holiday season. With some knowledge and a little effort, you may extend their life in our environment through much of the year. For more information on poinsettias, see this Ask IFAS document, or contact your local extension agent for additional information on this and any topic regarding your gardens and more.

A Nice Cup of…Camellia?

A Nice Cup of…Camellia?

Residents of North Florida are no doubt familiar with camellias, the large, glossy-green-leaved shrub that flowers during the cooler seasons. Common varieties include Camellia sasanqua, which blooms from October through December (depending on variety), and Camellia japonica, which blooms January through March. Both make huge, showy blossoms that demand attention, with forms that range from wild-rose-like to stunning geometric formal patterns.

The popularity of these shrubs is not in doubt, but a cousin of theirs takes the prize as one of the most popular plants in the world. Not due to its flowers: this variety of camellia does bloom, but the leaves are most interesting to humans. It is grown in dozens of countries worldwide and global production is estimated at over $17 billion worth of these leaves. The primary product made from this plant is a beverage that is consumed more than any other drink except water. It is, of course, tea.

Camellia sinensis or “Tea Plant”. Photo courtesy of UF/IFAS.

Camellia sinensis was named by botanist Carl Linnaeus, “Camellia” to honor another botanist, Rev. Georg Kamel, who really had nothing to do with the plant at all, and “sinensis”, which means “from China”. You may be able to deduce where tea is native to.

The tea plant prefers temperatures from 65 to 86 degrees Fahrenheit, doing well in zones 7-9. It can survive freezing or slightly-below-freezing temperatures, though leaves may be damaged by frost. It enjoys moist conditions, needing around 50 inches of rainfall per year. China tea (variety sinensis), which produces smaller, more serrated leaves, prefers more light than Assam types (variety assamica), which have larger, less serrated leaves. Either variety can be grown as a shrub or small tree.

Propagation may be accomplished either by seed or cuttings; cuttings are the preferred method for reproduction, as seeds must be germinated before the seed coat hardens for best results. Caring for tea plants once established involves more frequent but light fertilization, mulching, and regular scouting for pests. Camellia sinensis is susceptible to mites, thrips, scale insects, and aphids, all of which are present in large numbers in our area. Luckily, most of these problems can be solved with an application of either insecticidal soap or horticultural oil, if control is even necessary.

Once a tea plant is large enough to harvest leaves from, it is the new growth which is plucked. The top 2-3 leaves are used either fresh or fermented for a period of time before they are brewed. Green tea comes from the fresh leaves of China type tea plants, while either China or Assam types may be used to make black tea. Black tea leaves are picked, wilted or crushed, and allowed to ferment. Fermentation darkens the leaves and is halted by heating, which also serves to dry the leaves for storage.

For more information on the tea plant, see our EDIS publication on Tea Growing in the Florida Home Landscape.

Camellia sinensis foliage. Where the tea is made! Photo courtesy of UF/IFAS.
Autumn Brings Changes in our Landscapes

Autumn Brings Changes in our Landscapes

The shorter days and cooler temperatures of autumn bring on changes in our shrubs and trees.

Most people expect to see changes in leaf color in deciduous trees and shrubs during fall. But some people become concerned when the leaves on certain evergreen plants begin to turn yellow with the change in the seasons. For many plants this is normal.

Azaleas may lose a few leaves now. These are the older leaves on the branches near the center of the plant. There is no need for alarm by the loss of a few older azalea leaves 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. Be sure to keep azaleas and other ornamental plants well-watered during dry weather that may occur from now through spring.

Other plants such as gardenias, hollies and camellias may have yellowing leaves now. But as with azaleas, these are the older leaves on the stem near the center of the plant. The mature leaves will drop from the plant from now until spring. This is only the normal aging of older leaves. However, be careful to not confuse this normal process with spider mites, scale, lace bugs, nutrient deficiencies, poor growing conditions or salt injury. Just keep in mind that this normal change in leaf color and leaf drop occurs on the older leaves generally during cooler weather – it’s a seasonal change.

Young red maple with fall foliage. Photo credit: Larry Williams

The leaves of sycamore trees have changed from green to brown by now. Although the sycamore is a deciduous tree, this phenomenon may not be caused by a change in day length or temperature alone. This change in leaf color in sycamores can begin in late summer. Many times, it is the result of sycamore lace bugs feeding on the leaves. By the time the damage is visible, there is little that can be done to correct the problem. However, this problem will take care of itself since sycamore trees will soon be dropping their leaves.

We do have some trees that exhibit beautiful fall foliage this time of year. A few to consider include hickory and gingko for their bright yellow fall foliage, black gum for its early display of brilliant red, purple or orange leaves and Chinese pistache for its late reddish-orange fall show. There are plenty of other good trees to consider for fall color here in North Florida such as dogwood, crape myrtle, Florida maple, sourwood, shumard oak and the list could continue.

Gardening with Native Plants

Gardening with Native Plants

The interest and use of native plants in the landscape in Florida and the southeastern U.S. has increased significantly over the last 20 plus years.  There are many benefits for including them in our landscapes including creating a wider biodiversity and enjoying the multitude of support for butterflies, wildlife, and unique color displays.

Choosing the plant species that works in landscape sites requires a few considerations like being adaptable to the site conditions, soil type and preparation, understanding the plant establishment needs, and finding plants regionally to your area. 

Bald Cypress with a Saw Palmetto understory. Photo courtesy of Stephen Greer.

Develop a landscape plan that includes addressing soil and site preparation as many landscape sites are altered during the construction phase with the soil being drastically changed.  In Florida many sites need soil backfill to raise the elevation for buildings, drive or parking areas to remain above flood challenges.  Choosing the right plant for the right place will need to include understanding the plants’ growing environments.  Do the plants perform best in well-drained drier areas or moister situations with slight flooding tolerances?  Native plants have acclimated to specific soil settings over thousands of years.  When selecting the plants for your landscape, perform a site analysis with soil texture, drainage, soil pH, hours of direct intense sun or shade in the growing season, air circulation in the growing area, and growing space available.  Doing your homework first can save a lot of money and frustration later.  Visit the local nurseries to see plant availability.  Just remember many landscape settings do not always match the natural habitats where many of these plants are established in nature. 

Native Muhly Grass. Photo courtesy of Stephen Greer.

Soil amendments will likely be needed to improve the soil conditions and provide optimal plant establishment and performance.  Most often the soil that brought in is sandy and nutrient poor with little to no organic matter.  In addition, the soils are compacted by heavy equipment during the construction phase.  These factors can create native plant challenges leading to poor growth and shortened plant life spans.  When the soils have been addressed according to plant needs the selected plants can be placed and the fun part begins by following the landscape plan.

With the landscape conditions likely altered with amendments, choose plants that can establish and grow successfully in these often more difficult conditions.  Florida red maples (Acer rubrum), Live Oaks (Quercus virginiana) and Sand Live Oaks (Quercus geminate) all can provide shade areas for future plantings.  Butterflies attach to and feed on butterfly weed (Asclepias tuberosa) and swamp milkweed (Asclepias incarnata).  Butterfly weed does well in well-drained sandy soils and swamp milkweed likes it moist.  These are just a few of the many plants out there to consider.  Just remember to visit your local nurseries and talk with them about native plants and availability.  Enjoy your gardening adventure.

What to Do in the Garden in March and April

What to Do in the Garden in March and April

Variegated shell ginger is a good choice for adding color to shaded areas of the landscape. Photo by David W. Marshall.

Variegated shell ginger is a good choice for adding color to shaded areas of the landscape. Photo by David W. Marshall.

 

 

What to Do in the Garden in March and April

Written by David W. Marshall, UF/IFAS Leon County Extension Agent Emeritus

Except for a couple of freezes, it has been a relatively mild winter. But those freezes were cold enough and long enough to kill many tropical plants almost to the ground. Will we have more freezes? It’s possible, though after we reach mid-March, the probability drops significantly.

Some plants, such as this firebush, had stems killed back to the ground by the cold and will re-sprout from the root system. Photo by David W. Marshall.

Some plants, such as this firebush, had stems killed back to the ground by the cold and will re-sprout from the root system. Photo by David W. Marshall.

So, when can you start cleaning up all the cold damaged plants? You probably have the urge to do it as soon as possible, as the brown foliage and stems are a little depressing. Many of us have lots of cold-damaged plants and we want to get the cleanup finished. First, though, examine the plants to determine the extent of the cold damage. Scrape the bark with your fingernail or use a pocketknife to see if the tissue beneath is still green or if it has turned brown due to cold damage. In many cases, you will find that the stems have been killed back to within a foot of the ground. On other plants, you may find that some of the stems still appear green higher up and you may not have to cut them back quite as far. If that’s the case, you may wish to wait until mid-March to cut these plants back. In case we have another hard freeze, the damaged growth may offer a little insulation to the undamaged parts of the plant. With most plants there’s no real need to cut them back until the new growth starts popping out, probably in late March.

The stems of butterfly gingers can be completely removed now. Many of these will just pop off when pulled lightly. Others may have to be cut, but it won’t hurt them. Variegated shell gingers, in many cases, will still have some undamaged growth mixed in below the brown leaves. You won’t kill a well-established shell ginger by cutting it back now, but because of the insulating effect of the brown leaves, it’s probably best to wait until mid-March to cut them back.

Azaleas and camellias, typical of a North Florida spring, were blooming by late February this year. If you don’t have some of these in your yard, now is a good time to plant. Photo by David W. Marshall.

Azaleas and camellias, typical of a North Florida spring, were blooming by late February this year. If you don’t have some of these in your yard, now is a good time to plant. Photo by David W. Marshall.

You may have other shrubs that you wish to prune now also. Wait to prune spring bloomers like loropetalum and azalea until after they finish flowering. Some overgrown shrubs may need to be cut back hard to rejuvenate them, and if you do it now, they will have longer to recover. Before crepe myrtles start putting out new leaves, work on the shape of the tree. Remove poorly placed rubbing and crossover branches by cutting all the way back to the trunk or branch from where they grow. Don’t, however, top the tree unless you are purposely trying to pollard the tree and completely understand how to do it correctly. Otherwise, you will likely end up with a mess.

In mid-March, be prepared to plant warm-season vegetables such as tomatoes, snap beans, pole beans, lima beans, sweet corn, southern peas, squash, and watermelons. So, make sure you have the garden tilled before then. If you wait until April or May to plant, your harvest will be later and the insect and diseases will get much of the crop. Warm-season herbs can be added after mid-March.

Don’t be overly anxious to fertilize your lawn, especially if you have centipede grass. Wait until at least mid-March. Make sure the lawn has been fully green for three weeks before fertilizing. If this pushes you into April, fine. It’s better to fertilize too late than too early. Centipede lawns that are fertilized too early often have spring yellowing problems. St. Augustine grass is more forgiving, but don’t fertilize it either until at least mid-March. Use 6.7 pounds of 15-0-15 fertilizer per 1,000 square feet of lawn area. If the fertilizer doesn’t contain at least a third of its nitrogen in a slow-release form, though, cut the application rate in half.

Most of the weeds in the lawn now are winter annuals that will die out as the weather gets hotter. Just keep your lawn mowed regularly until they do. If you usually still have problems with weeds in the summer, though, you could use a pre-emergent herbicide to reduce the emergence of the summer weeds.

To keep fire ants out of your yard, broadcast a bait formulated product over the entire yard, according to the label directions. Plan to treat again in fall. You can quickly apply the bait using a small hand spreader available from your garden center.

Now, before it gets hotter, add some colorful camellias to your landscape. Photo by David W. Marshall.

Now, before it gets hotter, add some colorful camellias to your landscape. Photo by David W. Marshall.

Now, before it gets hotter, add some colorful azaleas, camellias, roses, and loropetalum shrubs to your landscape. Also consider fragrant plants such as tea olives, banana shrubs, and sweet viburnum. The sooner you plant these in the spring, the quicker they will get established and grow.

Lavender trumpet vine (Clytostoma callistegioides), crossvine (Bignonia capreolata), coral honeysuckle, and Confederate jasmine are vines that flower during this period of the year. Now is a good time to plant them also.

Don’t forget groundcovers such as liriope, Lomandra, Mondo grass, Dianella (New Zealand flax), African iris, or any of a variety of ferns. Groundcovers planted now will have a full growing season to get established. Groundcovers are often a good choice for plantings in front of the house where you don’t want tall shrubs.

Add some long-blooming seasonal color to your yard this spring. Once we reach mid-March the nurseries will be loaded with many possibilities. Petunias will give you a lot of color in sunny areas for about three months. After the summer rains start in June they normally decline. Pentas will hold up on through the summer and into fall. They prefer full sun but will take a little filtered sunlight too. Sunpatiens® will work in sun or shade and should hold up through the summer. Melampodium will give continuous yellow blooms in sunny areas through summer and into fall. Torenias, especially the trailing or vining types, are excellent for providing low-growing color in areas that receive morning sun but not so much harsh afternoon sun. But there are many other options, too, so visit a full-service nursery with knowledgeable employees that can guide you.

Pentas can be planted in mid to late March and will give color until late fall. Plant in full sun to light shade. Photo by David W. Marshall.

Pentas can be planted in mid to late March and will give color until late fall. Plant in full sun to light shade. Photo by David W. Marshall.

Also, later in the month, start planting perennials such as firebush, angel’s trumpet, cigar flower, and Turk’s cap so you will have color later in the season that will last into fall. These perennials will return each year, even if the tops get frozen back.

There’s no need to fertilize mature trees and shrubs that are growing well. But young plants which you’re trying to encourage to grow will benefit from an application of fertilizer now. The same 15-0-15 that you used for the lawn can be used on trees and shrubs, provided it’s not a weed-and-feed product with an herbicide. The exception would be with palms, especially if you’ve noticed that your palms haven’t been looking that healthy. Use an 8-2-12 or similar palm fertilizer that has four percent magnesium and micronutrients also. If you have a lot of palms in the lawn, just use this palm fertilizer on your whole lawn.

If you didn’t get around to fertilizing fruit plants in February, do it now. After mid-March is also a good time to plant new citrus trees such as satsuma, orange, or grapefruit. You have a full growing season ahead!

Anything that you plant now will need regular watering. That’s what they were receiving in the nursery. Remember that for several months, at least, all the roots will still be in the root ball that was in the pot, even after you put the plant in the ground. So, soak this root ball at least every other day. Don’t rely on a sprinkler system that only comes on once or twice a week. That’s not enough water for the limited root systems of new plants.

Written by David W. Marshall, an Extension Agent Emeritus with UF/IFAS Extension Leon County.