Tips for growing orange trees indoors

Citrus trees can be grown indoors successfully, but

Citrus trees can be grown indoors successfully, but only if certain criteria are met. (Credit: iStock)

Jessica Damiano

Jessica Damiano, Newsday columnist Jessica Damiano

Jessica Damiano is a master gardener and journalist with more

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DEAR JESSICA: We have a mandarin orange tree that was brought up from Florida as a tiny twig several years ago. Today the tree is about 6 feet tall, pretty wide and very green, lush and healthy. We keep it indoors, but it has never produced any fruit. Do you have any ideas about what might be wrong? Do you think it will ever produce fruit? -- Anna Dee, Merrick

DEAR ANNA: Citrus trees can be grown indoors successfully, but only if certain criteria are met. Although mandarin oranges are a bit more cold-hardy and drought-resistant than other citrus plants, your tree still is a tropical plant, so its environment should mimic the tropics as closely as possible.

First, it requires as much as 50 percent humidity, versus the 10 percent or so found in most New York homes over the winter. Keep the tree away from radiators and forced-air heating vents. Run a humidifier nearby or place the pot on a humidity tray (essentially a shallow pan that contains pebbles and water).

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Next, be sure the tree gets enough water. The only way to be sure how much moisture is around the roots is to feel it by sticking your finger all the way into the soil. Water when the soil is dry on the surface but still slightly moist at root level. Plant in equal parts of peat moss, sand and vermiculite, and ensure there are drainage holes at the bottom of the pot. Never allow roots to get soggy.

Keep the soil fertile by applying a slow-release 18-18-18 product or a fertilizer specifically formulated for citrus plants, following package directions, every three months.

Finally, citrus trees will not produce fruit without adequate sunlight. Keep your tree in a sunny spot outdoors over the summer, and bring it indoors in early September. Both moves should be done gradually, changing environment for increasing time increments over the course of a week before settling it in for the season, to avoid shocking the plant. Once indoors, set it near your sunniest window (western, northern or southern exposure) and keep the curtains open.

DEAR JESSICA: How do we control earthworms that moles are feasting on and ruining our lawn? -- John Herson, Smithtown

DEAR JOHN: It's important to remember that it's the moles, not the earthworms, that are ruining your lawn. Attempting to eradicate the earthworms from your soil would be like throwing out the proverbial baby with the bath water. As they wriggle underground, they aerate the soil and enable oxygen to reach roots, and the castings (excrement) they leave behind contribute an abundance of nutrients. Your efforts should be focused on eliminating the moles, not their food supply.

Before discussing methods that are effective against moles, I'd like to go over what doesn't work, because I suspect your problem might have been discussed at your holiday dinner table, at the barbershop or with your landscaper, if you have one -- and there are a lot of old wives' remedies out there that simply do not work.

Do not waste your time with mothballs, chewing gum, ultrasonic contraptions or windmills. Likewise, some bogus products are sold alongside effective ones on store shelves, which can lead to confusion. I'm most incredulous about grain-based baits -- because moles don't eat grains -- and infused peanut products, because moles don't have the right kind of teeth to chew nuts. Their diet consists mostly of worms for a reason.

Now on to the two methods that will work: baiting and trapping. There are several brands of baits on the market that look, smell and taste like worms but that also contain the active ingredient bromethalin. Tricked into believing they are actually worms, moles gobble them up and succumb to the poison. Your other option is to set traps for the moles. For deep mole runs, scissor-type traps are most effective; for tunnels closer to the surface, use harpoon-type traps. Neither is necessarily humane, but they get the job done.

DEAR JESSICA: I planted broccoli and cauliflower in the fall. The plants were shipped to me by the growers at what they said was the appropriate time for planting. I mulched them with straw as they grew and made sure they had plenty of water. While the plants looked healthy, I am afraid I missed any chance of actually harvesting vegetables. Did the grower send them to me too late? -- Pietro Piraino, Centereach

DEAR PIETRO: Cauliflower and broccoli seedlings should be planted outdoors 10-12 weeks before the average first frost date, which on Long Island is Oct. 15. So counting back tells us the ideal planting window is from July 23 to Aug. 6. Still, broccoli and cauliflower are somewhat hardy and can withstand a light frost, so planting a little later -- up to mid-August -- might not be a problem, depending upon the weather.