Annuals to Beat the Summer Heat

It’s that time of year.  School is out, hurricane season is in, and the mercury is up!  Gardens wilt by midday and gardeners retreat into the air conditioning long before then.  Unless you have your toes in the water on one of Northwest Florida’s beautiful beaches, it can be a miserable time to be a Floridian, for plants and people!    However, despite the relentless heat and blistering sunshine, low-maintenance, eye-catching color can still be had in the landscape.  When the calendar flips to June, I turn to my two favorite Florida-Friendly annuals to do the heavy lifting in my landscape:  ‘Diamond Frost’ Euphorbia, and the ‘Cora’ Vinca series.

‘Diamond Frost’ Euphorbia – Photo Courtesy Daniel Leonard

A relative newcomer to landscapes, the award winning ‘Diamond Frost’ Euphorbia is an amazing introduction from Proven Winners.  The ultimate in tough, ‘Diamond Frost’ does great both as a mounding accent in a container or as a standalone bedding plant in the landscape. Though its individual, teardrop-shaped, white flowers are tiny, the hundreds of them that open each day really pack a floral punch in the landscape!  One caveat: if planting in the landscape, I find ‘Diamond Frost’ to be most effective massed in groups of three or more.   Due to the daintiness of the flowers, a single plant can get lost among other garden inhabitants.  However, when done right, ‘Diamond Frost’ is a proven winner in any landscape!

Mixed container featuring ‘Diamond Frost’ Euphorbia – Photo Courtesy Daniel Leonard

 

Next, the ‘Cora’ series of Vinca (Catharanthus roseus), also introduced by Proven Winners, is an improvement on an old favorite.  Note: This species is also, on occasion, called Periwinkle.  However, do not confuse it with the spreading, purple-flowered, perennial groundcover of the same common name!  Gardeners in the South have been growing Vincas for years. This species is unbelievably tolerant of harsh conditions, sometimes even seen growing in sidewalk cracks!  However, the unimproved species had an Achilles heel:  susceptibility to Phytophthora, a devastating fungal rot disease.  ‘Cora’ overcomes this issue and is as close to a perfect bedding annual as you’re likely to find.  The ‘Cora’ series is composed of cultivars with pinwheel-shaped white, pink and lavender flowers, a color for everyone!  The kind (and clever) marketing folks at Proven Winners have even made ‘Cora’ easy to spot on retail nursery benches; just look for the plants in the hot pink containers!

‘Cora’ Vinca
Photo: Andrea Schnapp

Both of the above-described plants are extremely undemanding of gardeners.  Once established, little is required in the way of irrigation and fertilization.  To ensure success, water daily for the first week after planting, back off to a couple of times per week for the next two weeks or so and then watch ‘Diamond Frost’ and ‘Cora’ thrive with only rainfall for the rest of the summer!  Keep in mind, during periods of excessive drought, supplemental watering may be required to keep any plant, even drought tolerant ones, looking their best!  To meet the minimal nutrition demands of these plants, I incorporate a quality, slow-release fertilizer (for example, Osmocote, Harrell’s Polyon, or any other similar product) at planting.  These products last two or three months in our rainy, hot, humid climate and generally need a second application accordingly for full-season performance.  ‘Diamond Frost’ Euphorbia and ‘Cora’ Vinca also require full, blazing sun for maximum floral performance.  Don’t be shy about siting them in harsh, sunny places, even a few hours of shade tend to make leggier plants that flower less!

Mixed container with ‘Cora’ Vinca accent
Photo: Andrea Schnapp

When you need low-maintenance, season long color that can beat the heat, look for ‘Diamond Frost’ Euphorbia and the ‘Cora’ series of Vinca at your local nursery!  Stay cool out there folks and happy gardening!

Plant Cupheas for Summer Flowers, Hummingbirds, and More

 

Cuphea ignea
Photo courtesy: Gary Knox

Cupheas are perennials that produce bright orange, red, yellow or purple flowers all summer and fall.  Some species are called cigar plants due to their tubular, cigar shaped flowers tipped in red or yellow (like a lit cigar). Others are sometimes called firecracker plants because their cylindrical flowers are bright red or orange (looking like a firecracker). By any name, their nectar-filled, tubular flowers are widely known for attracting large numbers of hummingbirds, butterflies and bees. In addition, young stems of some species are reddish, further adding color and contrast to the usually narrow, lance-shaped green foliage.

 

As a group, cupheas grow best in full to part sun (the brighter, the better) and well-drained, moderately fertile soil. Cupheas are drought tolerant once established, but grow faster and larger with regular moisture and occasional fertilization. Their origins in warm climates allow them to thrive in heat, but likewise make some species sensitive to cold winters. Those that are frost tender along the Gulf Coast are best placed in a sheltered location in the garden. Cupheas are pest and disease resistant and are not invasive in Florida. They are not truly deer resistant, yet reports suggest cupheas are not favored by deer.

Cupheas are great summer performers in bright, hot and dry locations. Flowering begins in summer and continues through fall until short days and cool weather reduce flowering or frosts cause dieback. Along the Gulf Coast, cool winter weather slows them down, so re-growth doesn’t occur until mid to late spring, and flowering usually doesn’t begin until days and nights are warm. Growth and appearance of many cupheas are improved if plants are pruned or cut to the ground in late winter.

Over 200 species of Cuphea are native to Mexico and the warm-temperate and tropical Americas. Of these and their hybrids, the cupheas listed below are great summer-flowering perennials for the northern Gulf Coast.

 

Cuphea micropetala
Photo courtesty: Gary Knox

 

Cigar Plant (Cuphea ignea)

This fine-textured plant produces red to orange tubular flowers about an inch long. This cigar plant is hardy to about 20°F. It grows about 2 feet tall and 3 feet wide along the Gulf Coast, though it would be a larger, evergreen shrub in warmer climates. This cuphea tends to have lanky growth, so occasional summer pruning will stimulate branching which results in more dense growth.

 

Cigar Plant or Candy Corn Plant (Cuphea micropetala)

Flowers are 1.5 inches long, emerge pale yellow and gradually turn orange from the base upwards, offering a colorful, two-tone effect. Foliage is hardy to 25-30°F and this cigar plant is root hardy to at least 15°F. Stems should be cut back to ground level in late winter to keep the plant tidy. Clumps spread slowly outward by rhizomes, and the plant will reach 3 feet tall and wide along the Gulf Coast.

 

Cuphea schumannii
Photo courtesy: Gary Knox

 

Orange Cigar Plant or Schumann’s Cuphea (Cuphea schumannii)

This sprawling, floriferous cigar plant prefers moist, well-drained soil to thrive. Barrel-shaped, 1- to 1½-inch blooms are orange and yellow and sometimes have small purple petals at the tips. Flowers cover the branch terminals in the heat of summer and into fall. This plant is hardy in Zones 8 to 9 (at least down to the mid 20s°F). Unlike many other cupheas, leaves of orange cigar plant are oval- to heart-shaped. Stems grow 2 to 3 feet tall and readily flop or fall over. Plan to give orange cigar plant lots of room to sprawl through the garden!

 

Cuphea ‘David Verity’
Photo courtesy: Gary Knox

 

‘David Verity’ Large Firecracker Plant (Cuphea ignea × micropetala ‘David Verity’)

This floriferous hybrid produces flowers that are dark orange with a short yellow-orange flared tip and purple filamentts. Well-adapted to the Gulf Coast, this plant is foliage hardy down to 25-30°F and root hardy to at least 15°F. In Zone 9 this plant will grow as an evergreen shrub up to 4 to 5 feet tall and wide, but it will be smaller in areas where frost or freezes occur. This selection is believed to be a hybrid between Cuphea ignea and C. micropetala that was given in the mid 1970s to David Verity, then the manager of the UCLA Mildred Mathias Botanic Garden. It was subsequently named for him when later brought into commercial production.

 

‘Vermillionaire®’ Large Firecracker Plant (Cuphea ‘Vermillionaire®’)

This new hybrid appears to be a superior cuphea because it grows as a naturally compact plant that produces more flowers than other selections. ‘Vermillionaire®’ grows about 24 inches or more tall and wide with a compact, mounding habit. Orange tubular flowers are produced continuously until late fall. This cuphea is too new to know the full extent of its hardiness, but it is expected to be a perennial in Zones 8 and higher.

 

Mexican Heather (Cuphea hyssopifolia)

Unlike the previous cupheas, this plant has small purple flowers, and some selections sport white flowers. Another difference is Mexican heather’s finely textured, bright green leaves. Gulf Coast Zone 8 plants are usually killed to the ground in winter, often recovering by summer but resulting in a compact plant growing less than 24 inches tall and wide. In Zones 9 and higher, Mexican heather is a larger-growing semi-evergreen tropical shrub. Reported pests are leaf-chewing beetles (Altica and Colaspis spp.) and the twig-dwelling lesser snow scale (Pinnaspis strachani). Mexican heather works well for edging beds or sidewalks, helping to define and soften pathways. Cultivars include Allyson, Lavender Lace, Purple Nurple™ and the white-flowered Monga (Itsy Bitsy° White) and ‘White Whispers’.

Bat-Faced Cuphea
Photo courtesy: Gary Knox

Bat Face Cuphea (Cuphea llavea)

Each 1-inch flower consists of a purple tube lipped with two red, upright lobes. By viewing the flower with its tip facing you, it takes only a little imagination to see the two red lobes resemble large “ears” above the purple “face” of a bat, hence the name. Along the Gulf Coast, bat face cuphea grows mound-shaped 8 to 24 inches tall and wide, depending upon the selection. It is very heat and drought tolerant but requires better drainage than the other cupheas. Bat face cuphea is evergreen down to the upper 20s°F and root hardy into the lower 20s°F. Improved forms of bat face cuphea include the cultivars, Flamenco Samba, Georgia Scarlet, Mellow Yellow, Miss Priss, Tiny Mice®, Sriracha™ Pink, Sriracha™ Violet, Torpedo, Vienco° Lavender and Vienco° Red.

Florida Natives: Stokes’ Aster

Florida Natives: Stokes’ Aster

‘Mel’s Blue’ Stokes’ Aster. Photo credit: Mary Derrick, UF/IFAS Extension.

Florida is home to some of the most beautiful flowering perennials. An exceptional one for the panhandle landscape is Stokes’ aster (Stokesia laevis) as it is showy, deer resistant and easy to care for. Unlike other perennials, it generally is evergreen in our region so it provides interest all year.

Upright habit and profuse blooming of ‘Mel’s Blue’ Stokes’ Aster. Photo credit: Mary Derrick, UF/IFAS Extension.

The original species of Stokes’ aster has purplish-blue flowers but cultivars have been developed with flowers in shades of white, yellow, rosy-pink and a deep blue. The flowers are large, eye-catching beauties that bloom in spring and summer. They also last well as a cut flower. You will find that bees and butterflies will appreciate their nectar! Remove spent flowers after blooms have faded in order to encourage repeat flowering.

A location in your landscape that provides part sun with well-drained rich soil is best for this perennial. Stokes’ aster is native to moist sites so it does best with regular moisture.

Stokes’ aster attracts butterflies like this black swallowtail. Photo credit: Mary Derrick, UF/IFAS Extension.

As with many perennials, the plant will form a large clump after a few years; this gives you the opportunity to divide the clump in the fall and spread it out in your landscape or share the joy with your gardening buddies.

For more information:

Gardening with Perennials in Florida

 

 

 

 

 

Florida Wildflowers: Coreopsis

Florida Wildflowers: Coreopsis

Native Lanceleaf Coreopsis. UF/IFAS Photo: Thomas Wright.

Native Lanceleaf Coreopsis. UF/IFAS Photo: Thomas Wright.

In our demonstration garden we are enjoying the small but vibrant blooms of our state wildflower Coreopsis, also commonly known as tickseed. After many years of its use in the Florida highways beautification program, Coreopsis was adopted as Florida’s official state wildflower in 1991.

Florida can boast of 16 different species of Coreopsis that occur in the state with most blooming in the spring but some species blooming in the summer to later in the fall. Some of those species are rare, endangered or only found in very limited areas of the state, while others are quite common throughout the state.

Photo credit: Mary Derrick, UF/IFAS.

Photo credit: Mary Derrick, UF/IFAS.

Many lovely new cultivars have been introduced for our enjoyment by plant breeders through cross-breeding and selection. Some you can see in the accompanying photographs in this article.

Photo credit: Mary Derrick, UF/IFAS.

Photo credit: Mary Derrick, UF/IFAS.

Coreopsis is an annual or short-lived perennial that makes a great addition to your garden beds. And the bees and butterflies will enjoy them! The numerous flowers readily produce seed for naturalizing in the landscape. Plant them in a sunny spot in the landscape in evenly watered but well-drained soil. Removing the dead blooms will encourage plants to prolong their blooming; you can also save the seed for replanting in new areas of your landscape.

For more information:

History of Coreopsis as Florida State Wildflower

Gardening Solutions: Coreopsis

Florida Wildflower Foundation

 

Design Your Own Butterfly Garden

Design Your Own Butterfly Garden

Butterflies are not only beautiful to look at in your landscape; they serve as important pollinators and indicators of the health of our environment. Attracting them to your garden and incorporating some features to get them to stay and make it their home involves a little planning ahead of time for optimum results.

Queen butterfly. Photo credit: Milt Putnam, UF/IFAS.

Queen butterfly. Photo credit: Milt Putnam, UF/IFAS.

Choose a location that provides some protection from wind. Trees and shrubs that provide wind protection also serve as a safe harbor from rain and predators. The garden should be mostly sunny with some part sun areas. Ensure that any new plantings have access to a convenient irrigation source so they can be successfully established and maintained in good health.

Now you’ll need to choose the plants. Adults feed on the nectar of many flowering trees, shrubs, perennials, and annuals and, fortunately, there are usually many choices that will meet your site requirements and your taste preferences. In order to keep the butterflies in your garden, certain plants need to be available to serve as host plants for their young. Determine which species of butterfly is common in your area and that you want to attract. Most species have very few plants on which the caterpillars can feed so those host plants need to be chosen wisely. Determine whether any of the plants you already have are host plants and they can be integrated into your butterfly garden. For example, cassia is a host plant for the Cloudless Sulphur and citrus is a host plant for the Giant Swallowtail.

In choosing your nectar plants, select those that are native or Florida-Friendly as they are lower maintenance, giving you less trouble in the long run. Choose plants that have flowers in a variety of color, size, and shape. Different butterflies like to feed at different elevations, so choose trees, shrubs, perennials, and annuals of varying heights. In order to have nectar available throughout the time when the butterflies occur, include plants that bloom at different times of the year. And include some plants that bloom from spring to late fall, like pentas or moss verbena.

Larger plants should be placed in the background with smaller plants layered in the foreground.  When you plant smaller annuals and perennials, place them in masses to better attract the butterflies.  Consider placing host plants in an area that is in close proximity to the nectar plants, but in an area of your garden that is not a focal point. Host plants can get quite ragged looking from hungry caterpillars!

Good maintenance practices will enhance the health of your garden. Regular fertilization and irrigation if needed will help keep your plants in bloom and healthy; healthy plants are less susceptible to disease and pests. Avoid pesticides as they may harm the very creatures you are trying to attract. Never use Bt or systemic pesticide.  If you must, target a pest with lower risk oils or soaps and then only treat the affected plants. Lastly, be aware of beneficial insects that will help you achieve satisfactory control of a pest.

Now that your plants are placed there are several things to do to make your butterfly garden complete. Add a spot where water can puddle on the ground for the adult butterflies to drink. They require minerals from the soil that get dissolved in the water. Also add a rock or log in a sunny spot where butterflies can rest and sun themselves. And consider placing a comfortable place for you to sit and enjoy the beauty of your garden and its inhabitants!

For more information:

Butterfly Gardening in Florida