Our Garden Editor offers tips and ideas for June gardening.
Big, Bright Blooms
Mandevillas offer beautiful flowers from summer until frost. Plant them to grow on a trellis, arbor, or fence. They also work well in large containers and can climb up a topiary frame. Great selections include ‘Red Velvet’ (red-pink); ‘Sun Parasol Crimson’ (red); ‘Alice du Pont’ (pink); and ‘Sun Parasol White’ (white). Mandevillas bloom best in full sun and love the heat and humidity of summer. They climb by twining. Plant them in fertile, well-drained soil. Feed them regularly for lots of blooms. Use a water-soluble fertilizer such as Schultz All-Purpose Liquid Plant Food 10-15-10 or a granular, slow-release product such as Osmocote Outdoor & Indoor 19-6-12. You can also try a continuous slow-release fertilizer such as Dynamite Organic All-Purpose 10-2-8.
The summer solstice comes on June 20, heralding the beginning of summer. If the heat has not been enough of a reminder of the season, take a moment each week to write down observations of your garden in a notebook. Keeping a journal is a great way to learn about gardening.
As your tomato plants prosper, secure them with a product such as Sturdy Stretch Tie, which we found at www.plantitearth.com. This tape stretches as your plants grow without harming the stems. It also works well for other summer favorites such as Oriental Hybrid lilies, dahlias, and gladiolus. You can also find it at your garden center.
Try this successful combination. Take a 24-inch-diameter pot, plant one purple fountain grass (4-inch pot), two ‘Lucky Honey Blush’ lantanas (4-inch pots), and one purple heart (4-inch pot). Place in a location that receives full sun. Enjoy!
As the days become warmer and plants in your pots fill out, they may need more water. The next time you finish watering with the hose, fill up your watering can. This way you can easily give your plants a quick drink between regular waterings if they need one, and you won’t have to drag out the hose every time.
Fertilize warm-season grasses such as Bermuda, St. Augustine, and Zoysia now. Use PennGreen All in One Fertilizer 16-4-8 or Scotts Southern Turf Builder 26-2-13 at this optimum growing time. For centipede, use a specially formulated fertilizer such as Sta-Green Centipede Weed & Feed 15-0-15
They’re not just for South Florida. Plant tropicals such as ‘Red Velvet’ mandevilla, yellow bells (Tecoma stans), bush allamanda (Allamanda schottii), or peregrina (Jatropha integerrima) in the ground (even in North Florida), and they will flower until late October. Other good choices include firebush (Hamelia patens) and parrot heliconia (Heliconia psittacorum). Tropicals perform well in our heat and humidity. Winter freezes can kill them to the ground, but with a little heavy mulch for winter protection, they can resprout the following spring. You can also grow tropicals in large containers. Bring the pots inside a garage or other protected location on nights that drop below 32 degrees for several hours. Move them back outdoors the rest of the time.
North and Central
• Beautiful lawns--Keep an eye on your sod. As summer rains begin, so can gray leaf spot disease on St. Augustine grass. The disease favors periods of 12 or more hours of moisture or high humidity. Avoid watering the lawn in the evening. Also avoid fertilizing or weed control now, as these practices can increase the severity of the disease. If the disease becomes severe, call a professional lawn-care company to apply effective fungicides such as Insignia or Heritage.
• Crepe myrtles--Plant these stars of summer in full sun for the best flowering. Your choice of selections should depend not only on color but also on the size and form needed. For example, ‘Sioux’ has a very upright, narrow form, whereas ‘Natchez’ forms a broad, rounded tree. Selections such as ‘Acoma,’ ‘Cheyenne,’ and ‘Tonto’ don’t grow taller than 12 feet.
• Annuals--Good ones that will tolerate the heat include purslanes (shown at left), trailing torenias, melampodiums, fanflowers (Scaevola aemula), scarlet sages, ornamental peppers, sun coleus, ‘Brazilian Red Hots’ alternantheras, and Profusion Series zinnias. Central and South
• Oleander care--Ragged or chewed leaves usually indicate damage from oleander caterpillars. If the caterpillars are still clustered together on the affected limbs, just prune out those limbs. If the caterpillars have spread, spray with a Bacillus thuringiensis insecticide, such as Dipel, or drench with Bayer Advanced Tree & Shrub Insect Control.
• Royal poinciana--Plant one of these spectacular flowering trees, and enjoy the masses of red flowers every summer. It’s tolerant of most soil types and is a fast grower, reaching up to 40 feet tall with an even greater spread. It needs full sun to flower well.
Related: What to Plant in Florida in May
Mandevillas such as ‘Red Velvet’ (red-pink), ‘Alice du Pont’ (rosy pink), and ‘Summer Snow’ (white) love to twine and grow well on trellises and pyramidal forms. Allamandas are known for their bright yellow blossoms but also come in purple, white, and chocolate shades. All like rich soil and can be maintained in containers sunk into beds during the warm season and then given protection in winter. Coral vine is a South Texas standby. Airy and graceful, it comes in pink, dark pink, and white. Flowers begin to appear in late summer and attract hummingbirds.
• Garden rooms--Outdoor kitchens, fireplaces, and dining areas should be located where they will be used and enjoyed to the fullest. If privacy is needed, add hedges using ‘Dwarf Burford’ hollies, dwarf cherry laurels, or sasanqua camellias. Accessorize your new room with a large, self-contained fountain or specimen container plants. Choose practical outdoor furniture to complete the setting.
Central, East, and South
• Turfgrass--St. Augustine, Bermuda, centipede, and Zoysia grasses can all be grown in our region. St. Augustine is shade tolerant, but it uses more water and is less drought resistant than Bermuda or Zoysia. Common Bermuda grass can be started from seed and grows fast. Zoysia provides a beautiful, fine-textured lawn but spreads slowly and needs plenty of sunlight to thrive.
• Chrysanthemums--These perennials thrive in our region but should be divided and reset at this time. ‘Country Girl’ (pink) is among the best with its daisy-like pink flowers and yellow centers. Be sure to pinch them back by removing the top several inches of growth several times until about September 1. You will be rewarded with drifts of blossoms during mid- to late-fall.
North and East
• Hydrangeas--These plants thrive in partially shaded areas that have adequate moisture. French or mophead hydrangeas can be pink, blue, white, or nearly red. ‘Endless Summer’ and ‘Mini Penny’ are newer selections that rebloom from summer through fall. Double-flowering oakleaf hydrangeas, such as ‘Snow Queen,’ are particularly handsome and are popular as dried flowers.
Central, West, and South
• Mulch--Add mulch to vegetable and ornamental areas to conserve moisture and limit weeds. Grass clippings, coastal Bermuda grass hay, and shredded bark all work well. Mulches also reduce soil temperatures and help keep plants growing during the hot weather.
"Around Your Garden" is from the June 2008 issue of Southern Living.