Help arrives for the summer garden
Q: I have a question about the growth habits of orchid cactuses. Most older “leaves” remain green but look a little shriveled, though I try to be careful about watering. The soil is always kept moist, and I only water when it’s dry up to my first knuckle. The weird thing is that there’s new growth, even on these shriveled leaves, and it’s always shiny and firm. Is this just how these plants grow?
A: Epiphyllum, also known as orchid cactus or night-blooming cereus, is a true cactus of a different sort: They are found in the rainforest. Unlike other cactuses, their roots like to be moist, but not too wet. However, like other cactuses, they do not have leaves. What we call leaves on this plant are long, flattened, modified stems. This is important to keep in mind since certain care changes will not alter the changes that have occurred in these stems. Stems can wrinkle if they get sunburned (usually shows as yellowing), experience temperatures near freezing, or if they have had insufficient water. It sounds like you are doing the right thing with watering, but you may want to reassess to be sure they were not left
to dry out too much. The leaf look-alikes will not unwrinkle, as many other houseplants will do. New, healthy ones coming up are a good sign that favorable conditions have returned.
Q: Why are new leaves from my basil plant curled and wrinkled? They are outdoors in plenty of sunlight with light shade and have not been pruned. There is no noticeable mold on the tops or bottoms of leaves.
A: Basil, in general, loves the sun, warm temperatures and moderate moisture. Basil also needs to be pruned, whether it is used or not. Pruning once it gets about 8 to 12 inches tall will encourage a fuller plant that provides a longer and healthier harvest. By process of elimination, your basil does not appear to have the typical diseases of downy mildew or fusarium wilt. Considering it is close to blooming, plus all the rain we had, followed by heat and humidity, it may just be getting to the end of its life cycle.
Q: I have a 4-foot-tall gardenia that was damaged in February. I left it alone until June, by which time it had some new leaves and a few blooms. During our heavy rains, I fed it a couple of times with granular fertilizer for acid-loving plants and a soil acidifier (copperas sulfate). Within a week, there was a ring of burned grass, and the shrub looks burned.
There are few leaves left, and most of them are brown and shriveled. What can I do?
A: Gardenias are great landscape plants that perform well in full sun or partial shade. This broadleaf evergreen with its waxy foliage and sweetly scented flowers is a joy to have in any landscape. They can be finicky at times since they prefer an acidic soil, usually in the range of 5 pH to 5.5 pH, most will perform well up to 6 pH. From your description, it sounds like you may have overfertilized the plant. Gardenias grow well with two applications of fertilizer per year; the first in February or March and the second in September. Adding too much fertilizer too often can lead to root damage and poor plant performance and the type of reaction you are seeing. A soil test to confirm the current pH would be a good first step to identifying the problem. The application of copper sulfate may have also negatively affected the soil, resulting in the burned grass. Until you have the results of the soil test, I would not apply any additional products.