Bob Albanese, Extension Specialist, Pinellas County Extension
Now that we are coming into the end of spring and, with a bit of luck into the beginning of our summer rainy season, you may be noticing that the winter annuals you planted are just past peak color and starting to look a bit shabby. It is time to pull them out and toss them into the compost bin (even though you may be able to get a few more weeks out of them). All that green material and moisture in the leaves will make great compost to add to the flower beds. While the weather may seem like summer we still have a few weeks left that are cool enough to get summer annuals established before the real heat arrives. When the rain starts in a few weeks (again with any luck) it will be just in time to take over the chore of watering through the summer. When choosing summer annuals you should be sure to match the needs of the plant to the demands of the site (growing needs vs. growing conditions). Remember “right plant right place” is one of the most important parts of Florida Friendly Landscapes and gardens. Unlike landscape beds annual beds usually do best if they are left without mulch or only very lightly mulched. What I like to do to give the appearance of a mulched bed is to mulch the outside 12 inches of the bed while leaving the middle un-mulched. When planting I space the plants so that they will fill in completely and plant in a checker board pattern so that they grow together a bit faster. Another trick is to plant the set a bit higher than they are in the pots, as this helps to offset many root rot diseases.
Angelonia (Angelonia angustifolia)
There are several new hybrids of this lovely short lived perennial (colors include shades of purple, pink, bi-colors, and white), you can find it in small pots or gallon size plants, It grows in full sun to partial shade growing to about 18 inches tall and has few problems except the need for regular watering. Another plus is that it can easily be propagated by cuttings.
Beach Daisy or beach sunflower (Helianthus debilis)
This plant is a wonderful. It’s an extremely drought resistant native groundcover that thrives in full sun. It can be grown from seed or you can set out small plants. The spacing should be about two feet apart because it becomes easily established and grows quickly sprawling over a large area. Once established it grows to about two feet tall and will survive on rainfall in full sun. After 18 to 24 months the plants may become ungainly and show signs of old age; when this happens pull the offensive plant out, harvest and sprinkle the seed over the exposed area and wait for some rain to start the re-growing.
Dragon Wing Begonia (Begonia ‘Dragon Wing Red’)
This hybrid is a great show of color for locations from part sun to shady locations. Be sure to get them acclimated to the sun before the heat of summer arrives. They will top out at about 16 inches tall and bloom continuously. With proper care you should be able to have a great show of color into the winter season. Space the plants about 12 inches apart, remember to fertilize at planting time with a good 100% slow release formula and water them a few times a week. This plant is always a joy to see in the landscape.
Gaillardia (Gaillardia aristata)
This is one of my favorite plants for summer color. Not only are they so easy to grow you might call them “bullet proof”. They are great for attracting butterflies. They flower easily and profusely with delightful showy bunches of yellow and orange bloom. They establish quickly after planting and are quite capable of surviving on rainfall only. Full sun is best but they will tolerate half a of day shade and still bloom with a good show of color. Mature height is about 18 inches tall, spreading to about a foot wide. This is another one of those wonderful plants that once you have it in the yard you will most likely always have it because it t reseeds profusely assuring that the next crop is only a rainfall away.
Gazania Daisy (Gazania nivea)
Gazania daisies are a colorful fix if you need low growing color with exotic color and patterns in the blooms. They excel in full sun and are very drought resistant; rainfall is almost always adequate. The blooms open each morning and close each afternoon around 3:00pm, and once planted in the right location you should enjoy them for a very long time. The only down side of this lovely painted daisy is that they require dead heading (cutting off spent blooms) to encourage more bloom.
‘Mona Lavender’ (Plectranthus X)
Mona Lavender is a fairly new hybrid that blooms very well in part shade with regular water. You’ll need to deadhead it occasionally which at the same time will encourage fuller growth and more blooms.
New Look Celosia (Celosia argentea X)
Not all Celosia are durable enough to grow through our Florida summer heat and sun, “New Look” will perform and look great the whole time.
Ornamental Pepper (Capsicum annuum)
Peppers are not only surprisingly durable in our hot summer sun; plant them where there is good drainage and plenty of sun. They typically grow to be about 20 inches tall, frequently have attractive foliage and produce multicolor peppers in profusion.
Periwinkle/Vinca (Cathcartus X)
There are many new hybrids of this long time summer bedding plant in Florida. A well draining soil is a must for this plant and I strongly recommend planting the sets higher than the surrounding soil by about 10%. The once limited color range has expanded from only polka dot, white or pink to include grape, salmon, peach and others. Full sun is fine. Rainfall will be sufficient if established and with any luck they will hold up till the first frost or freeze.
Purple leaf Basil (Ocimum basilicum 'Purple Ruffles')
If you like deep purple and have affection for pesto, you might want to try this plant. When it is planted in a large grouping it is quite stunning. The foliage is spectacular all summer in full sun. They will need some supplemental watering but it is worth it! They grow to be about 20 inches tall and get very full/dense. As I mentioned earlier, at the end of the season you get the bonus of all that fabulous foliage which makes a delicious Pesto.
Purslane/Portulatca (Portulaca grandiflora)
A delightful very low growing very drought resistant succulent plant that bloom from late spring to early December, and are capable of surviving on rainfall. They are available in many colors and bloom in profusion in the full sun; the blooms open mid morning and close by 3:00pm. Mealy bugs and scale are occasionally pests.
Salvia spp. (Salvia X)
There are many different salvia that do well in the summer, some survive on rainfall and some may require supplemental water. There are many which thrive in full sun and several need a bit of relief from the full day of sun so partial sun is best for those. They are all great for attracting butterflies and humming birds. Another plus is that many of them will live here for years as long as you do a severe pruning at the end of the growing season to rejuvenate them.
Zinnia X (Zinnia X)
There are several new or “Improved” Zinnias for our summer season, and they are all very drought resistant. One of my favorites is a small mounding plant called ‘Zinnia liniarus’. It thrives in full to partial sun make a mound about 15 inches round, blooms continually and is relatively trouble free. The flowers come in a limited color range creamy white and yellow. A new hybrid has larger blooms and pink flowers, unfortunately I have not had first hand experience growing it so I am not sure how well it will perform in our summers.
The link below is to the UF trial gardens in “G”-ville, the “warm season” annuals are what we would pant here in central Florida.