The description you give is a textbook example of fungal growth, which can be controlled by fungicides labeled for centipede grass. As always, be sure to read the label before applying any chemical to your lawn. Centipede grass is a low-maintenance grass that does not respond well to excessive use of fertilizer, especially nitrogen. Centipede grass is a paler green than St. Augustine. If you fertilize it with high levels of nitrogen, it will temporarily "green up," but you will have future problems. It prefers the soil pH to be 5.0 to 5.5, which is very acid. If your soil pH is not low enough, the grass will appear yellow (because of a lack of iron). When the grass starts to yellow, most people add more nitrogen, which can potentially cause the grass to become susceptible to insect and disease damage. When you fertilize, use a fertilizer containing elemental sulfur, which will help lower soil pH. A good fertilizer program would include applying iron to the grass in April and July for high-maintenance lawns, or in May and August for low-maintenance lawns. Contact your local extension service for the University of Florida/IFAS publication on centipede lawns.

I recently purchased a flowering maple plant. Should it be planted in the ground or left in the pot? What other care is needed?

Your new plant has a maple-looking leaf, but that's the only resemblance to a true maple. Flowering maple (Abutilon spp.) is related to cotton, hibiscus, and okra. Each has a bell-shaped, colorful flower. Like many other members of the Mallow family, it is cold sensitive and is best left in the pot in central Florida. Gradually increase the size of the container as the root ball enlarges. Water when the soil surface starts to dry, which may be daily during the summer. Also feed at least every other week March through October and monthly during the cooler times of the year.

I have a beautiful gardenia bush. It has dark leaves and blooms often. However, the flowers are small. Are there different varieties of gardenias, or is my plant lacking something? Most of the gardenias I have seen are twice the size of the flowers on mine.

The popularity of the common gardenia or cape jasmine (Gardenia augusta), has led plant breeders to develop plants with varying flower and leaf sizes, fragrance, color, and growth habits. Plants with these variations are known as cultivars, or cultivated varieties. Unless your soil is exceptionally dry, there is no other likely reason for the small flower size, except variation as expressed by different cultivars.

Is this a good time to plant impatiens in a large pot on a shady porch?

Impatiens tolerate all but freezing weather. Just be ready to move the container indoors when temperatures in the low 30s are expected.

We have a lemon tree that produced hundreds of lemons this year. We have picked many, but an awful lot in various shades of yellow are still firmly attached to the tree. We have been told that you must pick every single fruit in order for the tree to produce next year. Last year the tree produced 3 lemons; the year before none.When should we take all the rest off?

You do not need to pick any of the fruits in order to stimulate flowering and new fruit set. New plant growth on both the Meyer and Bearss lemon trees are the source of new flowers and fruits. The heaviest growth occurs in spring and is usually followed by 2 smaller growth flushes later in the year. Thus, remaining fruits are 'moved' to older wood as the new flushes occur. New growth is stimulated by warmer weather and not hindered by left-over fruits. To take advantage of this physiological response, commercial growers often prune their lemon trees in order to stimulate new growth flushes and consequently higher yields. The variation in fruit color on your tree indicates fruits at different stages of maturity due to the 3 annual growth flushes. The increase in annual yields is proof that your tree is progressing well under your care.

Loquats or Japanese plums (Eriobotrya japonica) are a forgotten fruit for the most part. The tree grows throughout Florida and fruits in all but the very cold regions. The fruits are ripe when they turn from green to yellow or orange and soften. Not all are tasty varieties, but most have a pleasing flavor. 

The Florida Exotic Pest Plant Council (www.fleppc.org) lists Ruellia tweediana (Ruellia brittoniana) as a category 1 invasive pest. Their listing has no legal standing, but is a good guide to the plants we wish to eliminate or keep in check. Not a true petunia, Mexican petunia is native to Mexico. It spreads by seeds and underground runners known as rhizomes.

My palm tree fronds are being eaten away. The termite-like activity is entirely on the leaves. What is causing this?

The palm leafminer, also known as the palm leaf skeletonizer, is out of control in some neighborhoods. The tunneling between leaf surfaces that produces debris much like that of termites is the work of cater-pillars.

The insects cover themselves with a silken web which gives protection from predators and pesticides. Usually the damage is restricted to a few fronds that can be cut from the palms with minimal harm to the plant.

Sometimes numerous fronds are affected and the caterpillars seem to spread quickly. Obtain control with an insecticide labeled for chewing insects and follow instructions for palms or ornamental plants.

We have several pine trees around our Pine Island property and it is time-consuming to pick up several barrels of cones large enough to shatter lawnmower cutting blades. I’ve heard that female pine trees do not have pine cones, or not as many as male trees.

Fruit and seed production are the result of plants engaging in sexual activities known as pollination. Depending on the species, some flowers on a plant only produce pollens and are known as male flowers. Other flowers, when pollinated, produce fruits and cones and are known as female flowers. To complicate matters, some plant species have male and female flowers confined to separate plants which are considered to be either male or female plants. Although both male and female plants flower, only the female plants produce fruit. Examples of dioecious species (with separate male and female plants), include mahogany, southern magnolia, and the Canary Island date palm. It is more common, however, to have both male and female flowers on the same plant. All plants of these monoecious species will bear fruits or cones. Monoecious trees include slash pines, common throughout south Florida, black olives, oaks, and crape myrtles. Your pine trees are monoecious and cannot be separated into male and female trees. Your problem will continue unless selected trees are removed.

I have a potted gardenia which is not grafted and is outgrowing its container on my patio. Can I plant it outside in the ground and have it survive and thrive?

Most ungrafted gardenias will last only a short period in an average landscape due to problems with nematodes or soil diseases. Gardenias bred for landscape purposes are usually grafted on a nematode- and disease-resistant rootstock. You can enjoy your gardenia for a few more years as a container plant by either pruning it back or moving it into the next size container.

I bought a Musa zebrina 'Rojo' for its striking variegated color. The plant is in a container on an east-facing lanai, but gets full sun all day. It is thriving, but the leaf tops are now solid green. What changed the color?