Good News for Hoya Fans
by Monica Brandies
Hoya nummularioides, when grown outside in Florida. often blooms from spring through fall. Photo by Monica Brandies
Perhaps the most exciting addition to the University of South Florida Botanical Gardens in Tampa is the Hoya Hut. Although small, it has major importance.
“Hoyas are in demand these days,” says Tom Burress, owner of Brooker Creek Nursery in Odessa. Burress has been growing hoyas for 40 years, and has over 100 different species and hybrids that he sells wholesale.
The USF Botanical Gardens Plant Shop carries about 60 kinds of his hoyas, and Tom suspects they have the best selection of any retail place, certainly in the state and possibly in the entire country. They have plants in 5-inch pots for $6 and in hanging baskets that are ready to bloom for $15. Burress paid $15 for his first hoya 40 years ago, so prices are better than reasonable.
Hoya kerrii is called valentine hoya because of its heart-shaped leaves. Photo by Monica Brandies
Hoyas are also called wax plants or porcelain plants because the flowers look almost artificial, as if they are covered with wax. They were first brought to England from Australia by Robert Brown. He named them in honor of his friend, English botanist Thomas Hoy, who was gardener to the Duke of Northumberland from 1788 until 1809 and the first to bring this plant into prominence. Hoyas are native to southern India, where they are highly prized. They are in the milkweed family.
While most of the hoyas we see hang down from baskets, some will also climb and cling with small stem rootlets. Laurie Walker, Director of the USF Gardens, saw a gorgeous one growing up a palm tree at Selby Gardens in Sarasota. That is going to be her next project. In the meantime Laurie has one at home that hangs in an oak tree. They take very little care. She does not even take it inside during the winter. Many are quite hardy, but some are not. They are tropical and grow best when temperatures are between 60 and 80 degrees.
Hoya lacunosa is cinnamon-scented. Photo by Monica Brandies
Hoyas are treasured foliage plants. The leaves can vary from small to large, thin to thick, mildly textured to convoluted. They can be shiny, fuzzy, leathery, velvety, rough or smooth, or fuzzy on one side and smooth on the other. They come in all shades of green, some with pink and white edges or touches of silver, some with dark patterns or colorful centers. H. carnosa f. compacta ‘Krinkle Kurl’, with its convoluted leaves, is called Hindu rope for obvious reasons.
But it is the blooms that Laurie says “just blow me away.” Hers blooms abundantly through the warmer months and each cluster of “stars” lasts for several weeks. Just before they bloom, the star-shaped buds are quite amazing. Even then they don’t look real. As they open, they become a ball with many double stars. They usually have 20 to 30, sometimes as many as 60 stars in each umbel, though some have as few as two to four larger ones.
The USF Botanical Gardens Plant Shop carries a fabulous selection of hoyas. Photo by Monica Brandies
Some take way too long to bloom. Tom Burress says he has some that haven’t bloomed even after 20 years. He pointed out the small flower spurs on the flowerless plants at the Florida State Fair last winter that proclaimed how much they had already bloomed. For the most prolific flowers, never cut off these bloom spurs. Let them stay after the blossoms fade, for new buds will form at the same place.
Plants also will not bloom if the are not pot bound, so don’t repot them often and then only into a slightly larger container. Water them less during cooler weather when they are not in active growth. Too much warmth, water and food promotes vegetative growth instead of flowers. They are most likely to bloom during spring and summer. When grown outside in Florida, they are often covered with flowers in the fall as well, especially H. australis with white fragrant flowers, and H. nummularioides with pink fragrant blooms.
Hoya carnosa ‘Crispa’. Photo by Monica Brandies
Hoya carnosa is the most common hoya. I bought a valentine hoya (H. kerrii) with heart-shaped leaves, but not the one with the white border. I prefer variegated plants when I know I can grow them, but they are more difficult and I’ve killed a few hoyas, so I’m sticking with green for now. I’m probably not ever going to try the fishtail hoya, which Tom Burress says is the most difficult.
At USF’s Hoya Hut you’ll find a great selection, reasonable prices and lots of useful information. There are photos of the flowers you can expect on your plant if it isn’t blooming when you buy it, as well as a list of other qualities of each kind of hoya, such as the varied fragrances.
Monica Brandies is one of Florida’s most popular garden writers. Look for her books on Amazon.
© 2014 Monica Brandies. Originally published in Florida Gardening, Jun / Jul 2014. Reprinted by permission. All rights reserved.
Ways to make sure your hoyas thrive
Do not pamper them. Give them good care, but avoid constant handling.
Do not move or touch the plant during its blooming period.
Most hoyas do well indoors, outside in Florida or in a greenhouse.
Indoors, they like to be near a north window or under fluorescent lights. Outside, they like filtered light and should be protected from afternoon sun.
Soil: Tom Burress plants his hoyas in a mix of half cypress bark mulch and half Canadian peat with a bit of perlite. African violet soil with some added perlite will also work as a moist, well-draining, light soil.
Watering: Keep the soil moist in spring and summer; keep it dry, but not to the point of shriveled foliate, in winter. Misting the leaves frequently to clean them and increase humidity is okay, but STOP misting when the plant is budding or blooming.
Feeding: When growth starts in early spring, hoyas react favorably to feeding. Tom Burress uses Osmocote. A liquid solution can also be used, and a bloom booster can help in most cases. Withhold fertilizer in winter.
Lack of water or too much fertilizer will cause foliage to brown around the edges and the leaves may drop.
Pruning: Cut back long, stringy growth or prune as needed for climbing on a support.
Pests: Especially indoors, you should watch for mealy bugs and aphids. If found, spray with a mixture of half alcohol and half water. Do not spray with anything except plain water if the temperature is above 80 degrees. If plants are kept wet too long and a fungus causes spots on the leaves, spray with fungicide and repot.
Propagation: Hoyas root easily from cuttings taken from sprint into mid-summer. Cut stem pieces with at least 2 to 3 nodes. Remove the leaves at the base, dip in root hormone and insert into the rooting medium in a 3-inch pot. Put the pot in a zip-lock bag and seal all but one inch. Leave it be in the shade for 2 to 3 weeks or until you see new growth. They can also be rooted in warm water. A single leaf without a node will not produce roots. They can also be grown from fresh seed. Since they are very sensitive to damping-off disease, you may want to spray the medium with fungicide before you plant, and every 5 to 7 days until seedlings are transplanted.