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.

Summer Tasks

Summer Tasks

Summer should be the time to relax and enjoy the fruit of all the hard work performed in the landscape over the previous winter and spring.  However, there are still some essential tasks that need to be completed during the summer.  Perform them in short energy bursts early in the morning or late in the evening.

1. Aerate Your Lawn

If your yard is starting to look weak and thin, even with fertilizing and proper moisture, it may need aeration.  Aeration, which is creating channels into your lawn, allows water and nutrients to reach the deep roots of your grass more efficiently.

To test if you need to aerate your lawn, shovel up a patch of grass to a depth of at least four inches.  If the layer of thatch is a half-inch thick or higher, your yard would benefit from aeration.  There are self-drive aeration machines and tractor-pulled devices you can rent to make quick work of large areas.  For smaller areas, simply punching multiple holes with a pitchfork will do the job.

2. Fertilize

Gardener fertilizing yard
Commercial landscape fertilizer applicators must obtain state certification.

Turf grass often displays a yellow color during the mid-summer rainy seasons due to the heavy rains flushing nitrogen away from plant roots. If your lawn is looking sad and yellow, chelated iron can often give a temporary green-up. Iron is not a replacement for nitrogen, but it can work well during our summer rainy season.

If you soil test revealed a potassium or magnesium deficiency, summer is a good time to make the last corrective application.  Potassium (K) is an essential macronutrient. Fertilizer bags typically show the percentage of potassium in a product as the third number displayed on the front of the bag (e.g., the “8” in 16-2-8). Potassium acts as a “vitamin” for turf grass, increasing root strength, disease resistance and cold hardiness.

Magnesium (Mg), also a macronutrient, is essential for the production of chlorophyll, necessary for photosynthesis, and also plays a part in the movement of carbohydrates from leaves to other parts of the plant.

3. Don’t Mow Too Short

It’s a natural inclination to want to mow your grass as short as you can, so you have the longest time until you have to mow it again. However, giving your grass a buzz cut every time you mow can hurt your lawn over time.

While some turf grasses can be mowed relatively short, like Bermudas and some Zoysias, most grass types shouldn’t be cut shorter than two-and-one-half to four inches high.  Mowing shorter than that can damage the growth point and leave it susceptible to disease and pest infestation.  It can also dehydrate the grass and lead to long term damage.

5. Water Infrequently but Deeply

One common mistake made by many is watering too often and too shallow.  When only given frequent shallow waterings, grass will begin to grow their roots upwards to take advantage of the small amounts of water, which makes weak and unhealthy.  The grass becomes even more dependent on water and very susceptible to disease and insect attack.

Try watering only once or twice a week, but for a considerably longer time so that the water can penetrate deeper into the soil and encourage downward roots.  Ideally, each irrigation zone is calibrated to determine the length of time it take to deliver ½ – ¾ inch.  Then set the system to run every 3-4 days for that number of minutes.  While checking the irrigation delivery system, make sure the rain shut-off device is working and set to the same ½ – ¾ inch.

6. Prevent Mosquitoes

Summer rains on a nearly daily basis lead to lots of standing water. In less than one inch of water, hundreds of mosquitoes can hatch 3 -5 days later. Not only are these blood-sucking pests annoying, but they can also transmit dangerous diseases like West Nile and Zika Virus.  Even without disease, their bites are painful and irritating.

To prevent mosquitoes, make sure no standing water is allowed to remain in your yard, either in low points or in empty containers like flower pots or wheelbarrows.  Any amount of stagnant water is the perfect breeding ground for mosquitoes.  Take a walk around the yard, dumping out water and disturbing the oak and magnolia leaves that are acting a collection cup.  Treat birdbaths and water features with floating “donuts” specifically designed to kill mosquito eggs.

While getting tasks done in quick morning trips to the yard, make sure to keep hydrated.  Heat exhaustion can happen fast.

Plant of the Week:  Crossandra

Plant of the Week: Crossandra

Crossandra in a back porch containter. Photo courtesy of Daniel Leonard.

In Florida, selecting the right plant for a sometimes-shady spot can be tough.  Generally, plants that can handle the stress of even a few hours of direct summer sun are considered “full-sun” plants.  Many plants that are recommended for “partial shade” either don’t flower as well in shade as they would in sun or have a weak constitution and wilt with any direct sunlight.  For these problematic, sometimes shady, sometimes not spots, the plant Crossandra (Crossandra infundibuliformis) can be perfect!

Crossandra is a tender perennial (or annual depending on how cold our winters get) native to India and Sri Lanka and closely related to Shrimp Plant and Mexican Petunia.  Growing slowly to about 3’ in height, clad with deep, dark, glossy leaves that remind me of the Coffee plant, and flaunting vivid orange flowers, Crossandra plants certainly lend a unique, tropical look to landscapes.  Like its more well-known cousins, Crossandra can grow in full shade but really thrives with 3-4 hours of direct sun daily and lots of heat and humidity.  These characteristics make the species the perfect summertime Panhandle porch plant!   

Adding to the list of accolades, Crossandra is also super simple to grow!  Apply a slow-release starter fertilizer at planting, supplement monthly after that with a general-purpose garden fertilizer, water regularly, and enjoy stunning orange flowers all summer!  As a bonus, if you’re a fan of the University of Florida, put Crossandra in a Gator blue pot and have the most festive porch around just in time for football season to kick off in a few weeks! 

Happy Gardening!

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.

 

 

Plant Preparation for Changing Seasons!

Plant Preparation for Changing Seasons!

As October gets by us and November quickly approaches, I would like to include the preparation on What to Plant? And What to Do? Some great annual plant choices are digitalis (foxglove), petunias, and Shasta daisy. There are many daffodil bulb varieties for North Florida including the following: Carlton, Fortune, Silver Charms, Thalia, and Sweetness. We will be getting into more of the cooler days, so this is a good time to start bulb onions and salad crops such as arugula, lettuce, and spinach. Dill, fennel, oregano, and sage are all herbs that can be planted throughout the fall months.

Start preparing now so your fall garden will be full of dark leafy greens, multi-colored lettuces, and root vegetables of all shapes and sizes. Photo by Molly Jameson.

In lawns there are a few key things that can be done in October. It is possible to control winter weeds before they appear. This is the time to use preemergent herbicides when nighttime temperatures are between 55-60 degrees Fahrenheit for four to five days in a row. If a green lawn is desired, you can overseed with annual ryegrass when the daytime temperatures are in the low 70s. Remember, the lawn will still need to be watered and mowed to maintain a healthy ryegrass. Watch for fungus like brown patch and large patch disease. This can become active when the soil temperature is between 65-75 degrees Fahrenheit.

Hollies also attract bees to the landscape.
Credit: Beth Bolles, UF IFAS Extension Escambia County

And last but not least as you prepare for winter around the corner you can plant evergreen hollies that will make it through the cold and provide a splash of color with red berries. Gather pine needles that are dropping and use as a natural mulch, and this is the last month that strawberry plants can be established in a bed or a large container.