Garden Detective: Adapting a croton plant to the indoors

Reader Bob Delfino's 17-year-old croton (aglaonema).

Reader Bob Delfino's 17-year-old croton (aglaonema). (Credit: Handout)

Jessica Damiano

Jessica Damiano, Newsday columnist Jessica Damiano

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Jessica Damiano demonstrates how to repot a houseplant. Dig This!

DEAR JESSICA: I have had this plant for 17 years. I brought it indoors around Oct. 25. It flourished outside and looked great, but over the past four or five weeks the leaves began falling. The plant is now thinned out. I have it near a window all the time with the blinds up. Is there anything you could suggest? Am I doing something wrong? -- Bob Delfino, Huntington

DEAR BOB: Crotons are pretty tough plants that don't require very much in the way of care, so it could be that it's just getting used to being indoors. Sometimes they drop leaves while adjusting to a change in environment. However, it is possible that the indoor conditions aren't ideal.

As tropical plants, crotons require humidity, so keep them away from heating vents and radiators. (You might want to run a humidifier if the air is very dry.) Cold drafts also could be to blame, so if the window is drafty, move the plant farther away. You also mention that you've had the plant for 17 years, but not whether you've repotted it recently. They should be replanted into the next size pot (2 inches larger) every two years. Use a rich, sterile potting mix that will drain well.

Otherwise, just keep doing what you're doing, don't fertilize over the winter and be careful not to overwater. When the soil is dry (stick your finger deep into the pot to gauge the moisture level near the roots), water until water runs from the holes at the bottom of the pot. After 30 minutes, discard the water in the saucer and don't water again until the soil dries out. Good luck!

DEAR JESSICA: I have a dwarf lemon tree close to 40 years old. It usually gives me three lemons a year, but this year it has eight. It goes outside in March, and before it comes in in November, I clean the entire plant with Schultz insect spray and give it a good bath. But every year around January it becomes infested with scale. I try cleaning it with alcohol and Schultz, which claims to be safe up to the day of harvest. If that doesn't work, I take off all the leaves and deal with the bark and branches until I can put it outside. I have other large houseplants and try to keep them from getting infected. Where are the insects coming from, and why do they attack the plant indoors? I would love to plant it outside, cover it in winter and hope for the best but am afraid it would freeze. What can I do to get this plant through the winter months? -- Michele Ciociano, Oceanside

DEAR MICHELE: Scale is a small, flat, oval insect often misunderstood because it doesn't move for most of its life. After crawling in its infancy, the insect attaches itself to plant parts, where it's often mistaken for a growth, bark irregularity or disease. It may not be moving, but it's active, inserting a needlelike mouthpart into a leaf or stem and sucking the life out of it. And it excretes a sticky honeydew, which in turn encourages the growth of sooty mold, which makes a dirty mess of plants. If this has happened, wipe it away, as it can inhibit photosynthesis and attract ants.

Scale is not easily treated with insecticides because the insects have a waxy coating that protects them. I suspect your tree has gone through overlapping generations that you're noticing when you bring it indoors.

Picking scale off by hand is usually effective. The easiest way to do this is to give plants a bath. Mix two teaspoons of dish detergent (not soap) into a gallon of lukewarm water and wash the plant with a soft brush to dislodge scale, then rinse. If the alcohol-and-cotton-swab trick didn't work, you might opt for picking them off with tweezers. If these methods fail, insecticidal soap or a fine horticultural oil spray can be applied, but these products are only effective when scale is in the newborn, crawler stage. Follow label directions.

Removing the leaves altogether is a mistake: The plant needs them to produce food for itself, absorb sunlight and breathe. Without leaves, plants become stressed, which makes them even more susceptible to insect attack. And you are correct: Your lemon tree would not survive a New York winter outdoors.

DEAR JESSICA: I have an overabundance of moss growing in my flower beds. All areas of the beds get plenty of sunlight, and the plants are not too close together. I think my husband is watering too much. I plan to get the soil pH tested in the spring. If it's too acidic, what is the best course of action besides watering less? Twice last summer I removed all the moss -- tedious work for something that just grew back. I'd like to take care of this the right way once and for all.-- Kathleen K., Mineola

DEAR KATHLEEN: Moss is a living organism that thrives in moisture and indicates your soil likely has low fertility and poor drainage. Your husband may be overwatering, but that alone wouldn't lead to such a problem if the water was draining well in the soil.

I'm guessing the soil isn't draining well because it's too heavy (clay) or compacted. The drainage capacity of clay can be improved by incorporating generous amounts of compost, which will also add nutrients to the soil. Compaction can be alleviated with core aeration to improve water and air penetration into the soil so moisture doesn't linger on the surface.

If the area gets sufficient sunlight, I assume another risk factor for moss, too much shade, isn't an issue. Check that downspouts aren't directing water into the beds. If they are, reposition them toward better-draining areas. If a soil test reveals too much acidity, incorporate dolomite lime (follow package directions).

There are commercial products to eradicate moss, but, in addition to posing a danger to yourself, children, pets and wildlife, they may kill the other plants in your garden as well. What's more, they offer only temporary relief from moss if drainage, pH and fertility aren't corrected.

Garden club of the week

Long Island Daylily Society

Meets: Monthly on Saturdays at 1 p.m.

Location: Planting Fields Arboretum in Oyster Bay

Dues: $10

Contact: 516-759-6691, lidaylily.org

With more than 200 members dedicated to growing, promoting and enjoying daylilies, this club holds meetings and outings that include guest speaker presentations, tours of members' gardens, a public plant sale, members-only auction, periodic silent auctions and door prizes at most meetings. Annual events include a picnic, potluck lunch, luncheon and a daylily show accredited by the American Hemerocallis Society.