Q: I just inherited a 2-year-old tropical hibiscus from a friend. It is inside, in a room that is about 64 degrees and gets tons of diffused sun. It seems very happy except for the yellowing and falling leaves. I'm pretty sure it's fairly normal for many of the leaves to yellow and fall off after the shock of being outside and then bringing it in, abruptly. The last half of the branches are happy, green leaves and beautiful peach-colored blooms and buds.
My question is about when to prune this back and repot, as it is very leggy and root-bound. In the pot, the plant stands about 5 feet 6 inches, so it's pretty big!
Thanks for any help. I've never had a tropical hibiscus before.
A: What a nice inheritance! Prune the plant as you bring it into the house — you may need to prune it to fit your space.
Yes, unless you can give the plant a lot of sun during the winter — or if you use grow lights — it IS going to lose a lot of leaves and produce few flowers. But remember, hibiscus bloom on the new growth, so spring growth is the most important to you. During the winter, give the plant at least four hours of direct sun — a southwest window and a grow light would help.
Also, normal house temperature is fine for the winter.
Hibiscus like to be pot-bound to bloom well, so don't be too quick to repot. Instead, in the spring, remove an inch or two of the topsoil and replace it with new bagged soil with fertilizer. Do this as new growth begins in early spring. As a rule, fertilize during the growing months from March to October. If repotting is necessary, trim a few roots to relieve the girdling or circling of roots which can strangle the root system. Don't ever remove more than a quarter of the roots at a time.
Keep the humidity up to discourage pests, like spider mites and aphids. Don't let the plant stand in water. Use lukewarm water when watering so you don't chill the roots.
Did you know that hibiscus plants have been known to live for 40 years? You may have to write your inherited plant into your will!
Q: I have had a white flowering oxalis for three years now, and it is growing very well, except this year, after having it outside on our third-floor condo deck, I brought it inside. While it was outside, I noticed white spots on the leaves that got to be the size of a dime. I have sprayed it, but the spots keep coming and the leaves turn brown and eventually die. Help!!
A: Yes, it's rest time for many plants — the weather is getting colder, and the light levels are going down with every day. The oxalis probably has a fungus. Why not try drying the plant out and allowing the little bulbs to go dormant, so you can remove the leaves after they yellow? Wait a few weeks, then replant in fresh soil. You should have regrowth in a matter of a few weeks — and flowers soon afterward.
Q: I have a lot of cut flowers during the summer season. How can I make them last longest? Should one use those packets of dry chemicals from florist shops? What are they? You hear rumors of sugar, also bleach or fertilizer. What is cheapest and most effective if you have a lot of cut flowers? I want them to last.
A: There are many home recipes for cut flower preservatives, whether they are garden-grown or store-bought flowers. All include some sort of a disinfectant, like bleach, and some food for the cut flower, like a sugar (The packets from the florist contain basically the same thing, and are very convenient). All solutions assume that you follow certain basic rules for all cut flowers and greens.
The universal rule is cleanliness:
Use warm water in the vase — it is absorbed easily.
Use a clean vase, change water and wash the vase every few days.
Cut a half-inch off the stem every few days and cut stem on an angle. It will allow better water absorption.
Re-cut the stem every time you change the water to allow maximum water absorption.
Remove any foliage below the waterline to prevent rotting.
Keep flowers in a cool location — avoid the top of electrical appliances such as a TV or a microwave, as well as heat vents and radiators.
Keep flowers away from fresh fruit, which exude a gas that will cause them to mature — and wilt faster.
While you wait for next summer's crop of cutting flowers, here are three "kitchen flower preservative recipes" to try on bought flowers. Try any of these mixtures — they will work differently with different kinds of flowers.
2 cups Sprite or 7UP — not diet. (Note: It's an acid lemon-lime brand with sugar.)
1âÑ2 tsp. chlorine bleach
2 cups warm water
2 tbsp. lemon juice
1 tbsp. sugar
1âÑ2 tsp chlorine bleach 1 quart water
2 tbsp. vinegar
1 tbsp. sugar
1âÑ2 tsp. chlorine bleach
1 quart water
Q: My gorgeous, but fussy Christmas cactus finally decided to bloom — and I think it's going to be beautiful! It's loaded with buds — so I moved it to a place of honor in the dining room where it could be enjoyed in all its beauty. About three days after I moved the plant, I was horrified to see most all of the buds began to drop off the plant.
I was careful moving the plant. It's getting about the same amount of light as it had been getting at the window, and the temperature is about the same — normal room temperature — and so is my watering.
What could ever have made it drop? I'm so disappointed.
A: I hate to tell you, but yours is a common complaint. Everyone wants to display a beautifully blooming plant. When a budded Christmas cactus is moved from window to window, the buds turn toward the new light source. Leave them alone — or be very careful to notice if the light is coming from the back of the plant or the front — then duplicate the light angle. You might be able to save the buds if you quickly return the plant to its original window spot and face it the way it was growing. Otherwise, you will have to wait until next year's buds. Sorry about that!
This week's dirt
Do the holiday plants, poinsettias and other gift plants look sick? Are the leaves beginning to turn yellow, particularly near the bottom of the plant? Begin first aid immediately.
Hopefully, when you brought the plants home, you didn't allow them to get chilled.
Check the room temperature: Is the plant near a drafty window or door where it gets blasted by cold air? Or is it too near a heat source where it gets cooked? Is the fragile foliage touching the icy glass window? Then move it.
Take the foil wrapping off gift plants and check for excess moisture. Foil holds water and plants can easily rot if not drained. Water plants, but don't drown them; never let them stand in water for more than an hour or two. And try to increase the humidity in your dry house — everyone will benefit.
Is the plant getting enough light? Lots of filtered light is needed for blooming plants, but not direct sunlight.
Groom the plant, carefully removing dead or dying flowers and foliage.
With proper care, your holiday plants should stay beautiful for several weeks.
North Shore Gardener by Barbara Barger of Beverly is a regular feature of the Home North section. Reach Barbara by e-mail at email@example.com or write to her c/o Salem News, 32 Dunham Road, Beverly, MA 01915. Her Web site is www.nsgardener.com.