Heating up with Hardy Hibiscus

Each time I travel to central and south Florida and observe the wonderfully flamboyant tropical flora, I am reminded of the unique and frustrating climatic characteristics of Northwest Florida.  Our weather is tropical enough through the summer to sustain virtually everything our friends to the south grow, but winters north of the Big Bend are just cold enough to prevent long-term success with most tropical species.  However, the genus that is maybe most synonymous with tropical color, the Hibiscus (it even has its own texting emoji!), contains several species that are hardy through our winters.  The best landscape plant of these hardy Hibiscus species is creatively (sarcasm) called Hardy Hibiscus or Giant Rose Mallow (Hibiscus moscheutos) and is an absolute star in the Panhandle, bringing the beauty of the tropics to your yard!

Hibiscus ‘Starry Starry Night’ – Photo courtesy Daniel Leonard

Rose Mallow is a native perennial species that occurs in sunny wetlands across the eastern U.S.  This species can grow 7-8’ in height in its natural, unimproved state and possesses the largest flowers of any hardy perennial, some varieties easily eclipse 12” in diameter.  Rose Mallows bloom through the heat of our long summers and return reliably each winter unfazed by frost.  The flowers also happen to be a favorite of butterflies and hummingbirds and bring beneficial wildlife to the landscape.  These characteristics and the trend towards the use of pollinator friendly, low-maintenance native perennials in landscapes quickly made Rose Mallow a jewel for plant breeders and now virtually all major horticultural brands have a line of Hardy Hibiscus available at garden centers, in varying sizes, flower color and leaf color/form.  Recent breeding efforts have focused on introducing plants with enormous, richly colored flowers held on compact plants with attractive foliage.  The results have yielded two series and three individual cultivars that I consider superior selections and are more than worthy of inclusion in your garden:

  • Summerific® Series by Proven Winners. This series is comprised of four robust (up to 5’ in height) cultivars, ‘Cherry Cheesecake’ (bicolor magenta and white flowers), ‘Berry Awesome’ (purplish lavender flowers), ‘Cranberry Crush’ (a red you really have to see to believe), and ‘Perfect Storm’ (notable for its deep purple foliage).
  • Luna Series by Monrovia. This series is notable for its ultra-compact (3’ in height or less) size and characteristically large flowers.  It is also composed of four cultivars, ‘Luna Red’ (deep red), ‘Luna Blush’ (white, fading to pink near flower margins), ‘Luna Pink Swirl’ (pictured and my favorite, bicolor swirly flowers), and ‘Luna White’ (white with a red center).

    Hibiscus ‘Luna Pink Swirl’ – Photo courtesy Daniel Leonard

  • ‘Starry Starry Night’ by Walter’s Gardens. (Pictured) This cultivar combines dark purple to black leaves with swirled pale and dark pink flowers.  It has performed very well in my landscape and if I could only grow one, this might be it.
  • ‘Lord Baltimore.’ The classic, large growing cultivar with bright red flowers that is widely available and easily found.  An oldie (introduced in 1955) but a goodie.
  • ‘Midnight Marvel’ by Walter’s Gardens. A “hot off the press” new cultivar that is currently difficult to find due to popularity, though some online outlets have them available in small sizes.  This one is worth your patience.  Sporting deep red blooms on near black foliage, there’s nothing else like it in the landscape.

In addition to being gorgeous plants, Rose Mallows are extremely versatile in the landscape and could not be easier to grow.  Because the size varies so greatly (from the diminutive 30” tall ‘Luna’ series to the 8’ tall unimproved species), there really is a place for one in every garden.  I like to use the smaller cultivars in large containers to facilitate moving them around where their floral display has the greatest impact or to create a tropical effect where in ground plantings are not an option (pool decks, patios, etc).  The larger cultivars make spectacular specimen plantings in perennial and shrub beds and even make a really dense, striking hedge (just know they disappear in the winter).  Be sure to give them as much sun as possible, as this will enhance the number of flowers on each plant and darken the foliage on the cultivars with purplish/black leaves.  Too little sun will result in fewer flowers and lighter green foliage.  As wetland plants, Rose Mallows enjoy regular water, either from rainfall or irrigation; they will let you know when they need it – their large leaves readily wilt under drought stress, somewhat like Hydrangea.

For low-maintenance, native, pollinator friendly, cold-hardy tropical color, you need look no further than Rose Mallow.  These perennial shrubs come in all sizes and colors and fit any landscape!  Look for the above listed series and cultivars at better garden centers and online retailers and enjoy the oohs and ahhs elicited when people first get a glimpse of Hardy Hibiscus in your landscape!  Happy Gardening!

 

The Grass is Getting “Hungry”

The Grass is Getting “Hungry”

(UF/IFAS photo Thomas Wright)

Northwest Florida’s weather patterns can present challenges to maintaining a health lawn. Heavy rains promote fast growth and relentless sunshine causes lawns to fade.  In the last 200 days we have received at least 68 days of rain.  While the rest of Florida was experiencing record drought, the Panhandle was experiencing torrential downpours.  With every drop of rain your spring fertilizer is being metabolized by the lawn, reducing how many nutrients remain in the soil.  Even the best slow-release fertilizer will only last 3-4 months.  The message is: “It’s time for more fertilizer.”

A healthy lawn is an important component of the urban landscape. Not only do lawns increase the value of a property, they also reduce soil erosion, filter stormwater runoff, cool the air, and reduce glare and noise.  A healthy lawn effectively filters and traps sediment and pollutants that could otherwise contaminate surface waters and groundwater.  Lawns require nutrients throughout the growing season to stay healthy.  In Northwest Florida the growing season is typically April to October.

Proper fertilization consists of selecting the right type of fertilizer and applying it at the right time and in the right amount for maximum plant uptake. The type of fertilizer should be based on a soil test, available through UF/IFAS Extension. The timing of application and amount of fertilizer is dependent on the research-based recommendations for the grass species and the fertilizer analysis of the product being used.

Chart excerpted from Florida Friendly Landscaping publication

Select only a fertilizer that states that the product is for use on residential turf. Do not use a fertilizer meant for flower or vegetable gardens on lawns. By Florida Administrative Code, Rule 5E-1.003, the Urban Turf Rule requires that the fertilizers being applied to residential lawns are labeled for the site and the application rates be followed.  Typically, these products will contain both slow-release nitrogen and low or no phosphorus.  Slow-release nitrogen will provide a longer-lasting response from the grass and reduces the potential for burning. For more information on the Urban Turf Rule go to: http://www.edis.ifas.ufl.edu/pdffiles/EP/EP35300.pdf.

With frequent rain the soil is also losing iron. Keep in mind that the green fading to yellow appearance in your lawn may be an iron deficiency.  Before applying your summer fertilizer put out a liquid chelated iron.  It will improve the health of the lawn while you are trying to find a dry day to fertilize.  While it is necessary to water in fertilizer with ¼” of water to reduce burn potential and volatilization, never apply fertilizer when heavy rain is expected.  The rainfall over ¼” can encourage runoff and/or leaching of that fertilizer, which can be costly and environmentally harmful.

Not all Palm Fertilizers are the Same

It is common in Northwest Florida for palms to show signs of nutrient deficiencies. In general our sandy soil is often nutrient poor and available nutrients can easily move out of soils with frequent rainfall.  In landscapes where fertilization is occurring, often the wrong types of fertilizer are applied.   Fertilizer miss-application actually increases nutrient problems for the palm.

Palms can be deficient in many nutrients but the most common deficiencies we see in landscapes are from inadequate amounts potassium and magnesium. The simple solution would be to purchase a fertilizer labeled for palms to correct the problem.  The difficulty is that most easily available fertilizers for palms do not have the correct form of nutrients that are required for the problems.  With the exception of nitrogen, all other nutrients are in a quick release form so while the slow release nitrogen lasts for 2-3 months, all other nutrients have been used up.  In response, the palm is encouraged to grow by the nitrogen but does not have enough of the other critical nutrients to carry out vital plant functions.  What we see is often older leaves that are yellowing, browning, and die off before they should because the plant is pulling any available potassium and magnesium from old fronds to support new growth.  Without the application of proper nutrients to the soil, the deficiency can continue until even new fronds are affected or the palm dies.

The fertilizer used for lawns does not have all the slow release and correct forms of nutrients for the palms. Older leaves turn yellow and brown indicating potassium deficiency. Photo by Beth Bolles, UF IFAS Extension Escambia County.

There is a solution that will help keep your palms healthy and attractive. Make sure you choose a specially designed fertilizer that has all nutrients in slow release form.  Look for an analysis such as 8-2-12-4 (Nitrogen-Phosphorus-Potassium-Magnesium).  Also read further on the label for Polymer Coated Sulfate of Potash, Magnesium Sulfate (Kieserite), and Chelate (Iron EDTA).  These are the forms of nutrients that will be beneficial to your palms.

Look in the area ‘Derived From’ (outlined in blue) on your fertilizer label to find the forms of nutrients. Photo by Dr. Monica Elliott, US/IFAS Extension.

If you have a mixed landscape where the palms are planted in the lawn, be sure to keep all lawn fertilizers out of the root zone of the palms. Lawn fertilizers do not have the correct forms of nutrients for palms. Remember also that palms roots extend many feet beyond the palm canopy so your ‘no lawn fertilizer zone’ may be past the mulch ring.

The recommendation from the University of Florida is 1.5 pounds of fertilizer over a 100 square foot area. Broadcast this on top of the ground and lightly water after application.  In North Florida, you will likely apply the correct palm fertilizer about at least two times in May and end of August or 1st of September.  If you are not able to use a palm fertilizer with the correct form of slow release nutrients, it is best not to fertilize palms at all.

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!

Does Your Lawn Guy Need a License?

If your lawn and landscape care professional applies fertilizer as a part of his/her services, then the answer is yes. Since January 2014, the Florida Department of Agriculture and Consumer Services (FDACS) has required that all commercial fertilizer applicators have a Limited Fertilizer License.

UF/IFAS File Photo.

UF/IFAS File Photo.

So what does FDACS define as a fertilizer? You may be surprised at what is considered a fertilizer under the statute that governs this license. The following are included:

  • Lawn or landscape fertilizers
  • Organic fertilizers
  • Any product that contains plant nutrients including compost
  • Lime and all other products that influence soil acidity/alkalinity
  • Substances that promote plant growth
  • Any other substance that provides a soil corrective measure

In order to obtain this license, lawn care professionals attend a science-based training session called Green Industries Best Management Practices (GI-BMPs) that teach environmentally friendly landscaping practices in order to protect Florida’s water quality. These practices also save the homeowner money, time, and effort; increase the health and beauty of the home landscape; and protect the health of your family, pets, and the environment. The training is led by UF/IFAS Extension professionals. Attendees must pass a post-training exam and then can receive a license valid for 4 years.

In order to check whether your lawn care professional has a Limited Fertilizer License, check the FDACS site here. Every applicator must have his/her individual license.