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Tired of Turf? Try Groundcover Alternatives Instead!

If you’re like me, growing turfgrass is often more of a hassle than anything else.  Regardless of the species you plant, none tolerates shade well and it can seem like there is a never-ending list of chores and expenses that accompany lawn grass:  mowing (at least one a week during the summer), fertilizing, and constantly battling weeds, disease and bugs.  Wouldn’t it be nice if there were an acceptable alternative, at least for the parts of the lawn that get a little less foot traffic or are shady?  Turns out there is!  Enter the wonderful world of perennial groundcovers!

Perennial groundcovers are just that, plants that are either evergreen or herbaceous (killed to the ground by frost, similar to turfgrass) and are aggressive enough to cover the ground quickly.  Once established, these solid masses of stylish, easy to grow plants serve many of the same functions traditional turf lawns do without all the hassle: choke out weeds, provide pleasing aesthetics, reduce erosion and runoff, and provide a habitat for beneficial insects and wildlife.

The two most common turfgrass replacements found in Northwest Florida are Ornamental Perennial Peanut (Arachis glabra) and Asiatic Jasmine (Trachelospermum asiaticum); though a native species of Mimosa (Mimosa strigillosa) is gaining popularity also.  All of these plants are outstanding groundcovers but each fills a specific niche in the landscape.

Perennial Peanut Lawn

Perennial Peanut is a beautiful, aggressive groundcover that spreads through underground rhizomes and possesses showy yellow flowers throughout the year; the show stops only in the coldest winters when the plant is burned back to the ground by frost.  It thrives in sunny, well-drained soils, needs no supplemental irrigation once established and because it is a legume, requires little to no supplemental fertilizer.  It even thrives in coastal areas that are subject to periodic salt spray!  If Perennial Peanut ever begins to look a little unkempt, a quick mowing at 3-4” will enhance its appearance.

Asiatic Jasmine

 

Asiatic Jasmine is a superb, vining groundcover option for areas that receive partial to full shade, though it will tolerate full sun.  This evergreen plant sports glossy dark green foliage and is extremely aggressive (lending itself to very rapid establishment).  Though not as vigorous a climber as its more well-known cousin Confederate Jasmine (Trachelospermum jasminoides), Asiatic Jasmine will eventually begin to slowly climb trees and other structures once it is fully established; this habit is easily controlled with infrequent pruning.  Do not look for flowers on this vining groundcover however, as it does not initiate the bloom cycle unless allowed to climb.

Sunshine Mimosa

For those that prefer an all-native landscape, Sunshine Mimosa (Mimosa strigillosa), also known as Sensitive Plant, is a fantastic groundcover option for full-sun situations.  This herbaceous perennial is very striking in flower, sending up bright pink, fiber-optic like blooms about 6” above the foliage all summer long!  Sunshine Mimosa, like Perennial Peanut, is a legume so fertility needs are very low. It is also exceptionally drought tolerant and thrives in the deepest sands.  If there is a dry problem spot in your lawn that receives full sun, you can’t go wrong with this one!

As a rule, the method of establishing groundcovers as turfgrass replacements takes a bit longer than with laying sod, which allows for an “instant” lawn.  With groundcovers, sprigging containerized plants is most common as this is how the majority of these species are grown in production nurseries.  This process involves planting the containerized sprigs on a grid in the planting area no more than 12” apart.  The sprigs may be planted closer together (8”-10”) if more rapid establishment is desired.

During the establishment phase, weed control is critical to ensure proper development of the groundcover.  The first step to reduce competitive weeds is to clean the site thoroughly before planting with a non-selective herbicide such as Glyphosate.  After planting, grassy weeds may be treated with one of the selective herbicides Fusilade, Poast, Select, or Prism.  Unfortunately, there are not any chemical treatments for broadleaf weed control in ornamental groundcovers but these can be managed by mowing or hand pulling and will eventually be choked out by the groundcover.

If you are tired of the turfgrass life and want some relief, try an ornamental groundcover instead!  They are low-maintenance, cost effective, and very attractive!  Happy gardening and as always, contact your local UF/IFAS County Extension Office for more information about this topic!

Impatiens for Sun and Shade

Source: UF/IFAS.

 

Impatiens are a very popular annual, bedding plant that provide a nice burst of color in the landscape. The traditional Impatiens (Impatiens walleriana), or touch-me-not, is the one that most gardeners know as needing part shade, but there are also the New Guinea Impatiens (Impatiens hawkeri) that are able to tolerate more sun. In addition to being able to withstand more sunlight, the New Guinea Impatiens also have larger flowers and leaves. Another highlight of the New Guinea impatiens is their increased resistance to downy mildew, a major concern for growers of touch-me-nots, especially in south Florida.

 

While native to the Old World, Impatiens are not known to invade Florida natural areas but may reproduce by seed. Touch-me-nots are known to spread easily be seed. An interesting fact about Impatiens is their bursting seed pods that can send seeds several feet from the parent plant. This characteristic is what led to the scientific name Impatiens – for impatient – and one of the common names – touch-me-not.

 

May is a good time to plant Impatiens in north Florida. They prefer slightly acidic soil and should be planted at a 12-18 inch spacing. Impatiens work well as a border planting or in mass plantings. While New Guinea Impatiens tolerate more sun, they still would prefer some afternoon shade. Those growing in full sun will need extra care to ensure they remain well watered. An all-purpose plant food can be applied at monthly intervals for best performance.

 

Some common varieties of touch-me-nots include ‘Accent’, ‘Blitz’, ‘Carousel’, ‘Dazzler’, ‘Impact’, ‘Impulse’, and ‘Super Elfins’. Common New Guinea Impatiens varieties include ‘Celebration Candy Pink’, ‘Celebration Light Lavender’, ‘Nebulus’, ‘Equinox’, ‘Sunglow’, and ‘Tango’. The newer ‘Sunpatiens’ variety is quite popular and comes in different forms – compact, spreading, and vigorous.

Source: UF/IFAS.

If you have any questions regarding Impatiens, please contact your local UF/IFAS Extension Office or visit our EDIS website at www.edis.ifas.ufl.edu.

A Shrub that Likes it Shady

Almost every landscape has a problem area where the sun just doesn’t shine and many plants won’t make it, maybe it’s the north side of your house, under a small tree, or tucked away in an oddly-shaped alcove.  We all know the same old boring green choices that work well here (Holly Fern, Cast Iron Plant, etc.) but maybe you want something a little bit different, something that will provide a pop of color and interesting texture!  Look no further than a recent introduction, a whole-plant mutation discovered from the little-used Grape Holly (Mahonia spp.), aptly named ‘Soft Caress’.

‘Soft Caress’ Mahonia is a beautiful little evergreen shrub from the Southern Living Plant Collection (one of the best of the collection in my opinion) and really is a game changer for full-shade areas.  Some of you may remember the traditional Mahonia, also known as Grape Holly, from your grandmother’s lawn.  Those plants were coarse, spiny, produced messy purplish berries and often appeared generally unkempt.  ‘Soft Caress’ is a major departure from its parent.  Possessing finely-cut, deep green, bamboo-like foliage, this plant’s texture really contrasts well with many traditional shady species.  As a bonus, ‘Soft Caress’ sends up brilliant yellow-gold flower spikes in the dead of winter, certainly a welcome respite from the other barren plants in the landscape; although in this unusually warm year, the plants are just now blooming in the Panhandle.

Photo courtesy: Daniel J. Leonard

‘Soft Caress’ is advertised to grow three feet in height and width, a more manageable size than the larger traditional Mahonia species, but I’m not sure I’d take that as gospel, the three-year old plants (hardly mature specimens) in my parent’s landscape are already that size and show no signs of slowing down.  However, I’ve found you can easily manage their size with a once a year prune to slow down some of the more rapidly-growing canes.  Be sure to time the prune as soon as possible after flowering is finished as ‘Soft Caress’ blooms only once a year and produces its flowers on the previous season’s wood, just like Indica Azaleas and old-fashioned Hydrangeas.

The uses in the landscape for ‘Soft Caress’ Mahonia are nearly endless.  It pairs well with almost anything in a shady mixed shrub border.  It works nicely as a foundation plant against a porch or under windows on the north or east side of a house where it will be protected from hot afternoon sun; I have employed a grouping of the plants in this way in my own lawn with success.  It even thrives in containers!  If you want to show off some serious horticultural design skills, mix ‘Soft Caress’ in a large container on the porch with some like-minded perennials for a low-maintenance, high-impact display that you don’t have to replant each season.  All this shrub requires is partial to full shade, moist well-drained soil, and an occasional haircut to keep it looking tidy!  If you’ve been struggling to find a plant that’s a little more unusual than the standard garden center fare and actually looks good in shady spots, you could do a lot worse than ‘Soft Caress’ Mahonia. 

As always, happy gardening and contact your local UF/IFAS County Extension office for more information about this plant and other gardening questions!

Go Native: Rainlilies!

Go Native: Rainlilies!

Florida is home to many gorgeous and desirable native plant species. One to consider for your landscape is the rainlily, Zephyranthes and Habranthus spp. They are easy to care for and are bothered by few pests.

Cuban rainlily, Zephyranthes rosea. Photo: John Ruter, University of Georgia, Bugwood.org

Cuban rainlily, Zephyranthes rosea. Photo: John Ruter, University of Georgia, Bugwood.org

As the name implies, rainlilies do thrive when getting consistent rain or watering. A good soaking rain event will result in blooms within a few days. This love for moisture makes them perfect for rain gardens.

Atamasco rainlily, Zephyranthes atamasco. Photo: Jerry A. Payne, USDA Agricultural Research Service, Bugwood.org.

Atamasco rainlily, Zephyranthes atamasco. Photo: Jerry A. Payne, USDA Agricultural Research Service, Bugwood.org.

Plant the bulbs or transplants in full sun to part shade in moist but well-drained fertile soil. Let them be for many years in order to form large impressive clumps and that is when they flower the best. You can also separate the clumps every few years to colonize new areas and pass along to others. After the plants bloom they will reliably set seed that you can collect to start rainlilies in other parts of your garden. However, the seeds are viable for only a short time so you should plant them immediately.

For sources of plant material, try your local nursery that tends to carry native plants or through online sources.

For more information:

Rainlily, Zephyranthes and Habranthus spp.: Low Maintenance Flowering Bulbs for Florida Gardens

 

Challenges for Use of Glyphosate Alternatives in Urban Landscapes

Challenges for Use of Glyphosate Alternatives in Urban Landscapes

Florida home and yard. Home, house, stone pavers, walkway, yard, landscaping. UF/IFAS Photo: Tyler Jones.

Florida home and yard. Home, house, stone pavers, walkway, yard, landscaping. UF/IFAS Photo: Tyler Jones

Dr. Ramon Leon, Extension Weed Specialist, West Florida REC, Jay

Last year the International Agency for Research on Cancer (IARC) of the World Health Organization (WHO) classified glyphosate as “probably carcinogenic to humans.”  This generated a lot of controversy because the Environmental Protection Agency (EPA), the European Food Safety Authority, and recently a joint report between the Food and Agriculture Organization (FAO) and WHO concluded that glyphosate is unlikely to be carcinogenic in humans.

As a University of Florida/IFAS Weed Specialist, I have been receiving multiple phone calls and e-mails from homeowners, homeowner associations (HOA), lawn care companies and contractors, municipalities, and county managers requesting a list of herbicides that are “safer” than glyphosate. When I ask them the reason for this particular preference, all of them acknowledged that their concern originated from hearing about the IARC report.

The first point that I always explain to people concerned about this issue is that most of the scientific evidence indicates that glyphosate does not have a higher carcinogenic risk compared to many other substances that they are normally exposed to in their daily activities. The second point is that it is important to continuously monitor how chemicals we use affect our health and the environment in the long run.  The IARC report is a reminder that we should keep a close eye on glyphosate, the most widely used herbicide in the world, but it is not necessarily a call to stop using it, because at this point there is no direct evidence that it causes cancer in humans.

Very frequently, regardless of the technical details, many homeowners and citizens in urban areas are considering not using glyphosate in their gardens and landscapes, and they would like to use “safer” herbicides.

What do you mean by “safer?”

If you mean lower risk as a carcinogen, then most herbicides registered for use in urban areas would be acceptable because none of them are considered “probably carcinogenic” by IARC or any other regulatory agency. Therefore, you have multiple options to choose from. However, many of the conversations have lead to the statement, “No, I want something that is less toxic than glyphosate!

Toxicity in pesticides is predominantly assessed using the lethal dose 50 (LD50), which indicates the amount of a chemical that kills 50% of a reference population of test animals (e.g. mice, rabbits, rats). When the LD50 is high, this means that the chemical has low toxicity, and when the LD50 is low it is considered that toxicity is higher because small amounts of the chemical can cause mortality.  Glyphosate has one of the highest LD50s for herbicides. In other words, glyphosate is one of the least toxic herbicides available based on the LD50 standard. Therefore, if we want an alternative herbicide that is less toxic, we do not have any options for urban areas.

What about organic herbicides?

Many people associate “organic” with “safer.”  This can be misleading because it depends on how safety is measured. For example, there are multiple organic herbicides that are considered to have the same or even higher toxicity when compared with glyphosate, because many of them have irritant and corrosive properties. Furthermore, organic herbicides have dramatically different herbicidal properties that make them unlikely alternatives to effectively replace glyphosate.

Glyphosate has one of the broadest spectrums of control, so it kills many different weed species effectively. Also, glyphosate works systemically. This means that it is absorbed by leaves and then moves inside the plant to growing points, roots, and other propagating structures. This systemic effect increases the ability to kill relatively large plants. In contrast, the majority of organic herbicides have a contact effect, so they only kill the tissue they touch without being able to move inside the plant. Therefore, they are effective at killing very small plants (<2 inches tall). Large plants can suffer leaf burning after treatment with organic herbicides, and if the application is done properly, the user will see a lot of control shortly after the application (Fig. 1). However, the plants will soon recover and the control level will decrease because, unlike plants treated with systemic herbicides, they can produce new growth from tissues that were not directly expose to the herbicide.

Figure 1. White clover (4 inches tall) control after treatment with glyphosate and twelve different organic herbicides based on natural oil extracts from plants. The green bars represent the level of control 7 days after treatment (DAT) and the yellow bars indicate control 21 DAT.

Figure 1. White clover (4 inches tall) control after treatment with glyphosate and twelve different organic herbicides based on natural oil extracts from plants. The green bars represent the level of control 7 days after treatment (DAT) and the yellow bars indicate control 21 DAT.

 

Considering the lack of alternatives to replace glyphosate, if you want to stop using this herbicide, and you do not want to use any other synthetic herbicides, because their toxicity might be higher, then you need to recognize that weed management will be more challenging. It is unfair to ask lawn care companies or members of HOAs to stop using the tools they have to control weeds and yet expect “weed free” lawns, gardens, and landscapes. Controlling weeds in these scenarios without glyphosate and other synthetic herbicides will require more intensive use of mechanical control approaches and hand weeding. Also, if relying on organic herbicides, these herbicides will have to be frequently applied (probably once or twice a week) in order to kill the weeds at the right time (before they get too big). Also, all these activities will increase weed control costs and the results will likely be not as satisfactory. Thus, you might end up paying more to have lawns and landscapes that will have more weeds escaping control. If this is not acceptable to you, then you probably should be more open to consider the weed control tools we have available. Also, you should be more vigilant about what are the appropriate ways to use them to minimize their risks to humans and the environment, while obtaining the benefits that you are seeking. Otherwise, you should get used to seeing more weeds in the landscape, and to be fair… this might not be as bad as some people think.