How To Grow Citrus Trees Indoors

You may daydream of growing your own citrus fruits, but unless you're in the southernmost portions of the country, your chances of success are, sadly, fairly slim. However, you can grow many different dwarf citrus tree indoors. With their glossy leaves, fragrant flowers and edible fruit, they're a must-have for any plant lover. "There are several types of citrus trees that are easy-to-grow in containers," says Danny Trejo, founder of Via Citrus, a citrus tree grower in Florida. "They're actually the ideal patio plant. They can go outdoors for summer, then come back in for winter before nighttime temperatures dip into the 40s."

The most popular and easiest-to-grow dwarf citrus is Calamondin orange (Citrus mitus), a cross between a mandarin and a kumquat. It has several flushes of beautiful, fragrant flowers throughout the year, followed the formation of quarter-sized oranges. The entire orange, including the rind is edible, says Trejo. Other good options for beginners include the Meyer lemon (Citrus x meyeri) and the Key lime (Citrus aurantifolia).

How Do I Care for an Indoor Citrus Tree?

Of course, outdoors, citrus trees love soaking up full sun, which is considered six or more hours of direct sunlight. Indoors, you can place them on a sunny east, west or south-facing windowsill, but they'll do better with a grow light. Keep the light on for your plant for 8 to 12 hours, but not overnight, says Trejo. All plants need darkness, too, as part of their growth cycle. Also, don't allow the light to get too close to the plant or you may scorch leaves; read the manufacturer's instructions for how near it should be placed for various types of plants.

How To Fertilize Your Citrus Tree

It's also helpful to fertilize your citrus tree twice a year, around Memorial Day and Labor Day. Use a granular extended release citrus tree fertilizer, which generally is higher in nitrogen (N). Follow the package instructions, and don't use more than recommended.

How To Water Your Indoor Citrus Tree

A lot depends on environmental conditions. Our homes tend to be drier indoors in winter, so your citrus tree may need watered more frequently. Running a humidifier, or grouping other plants together, which can boost humidity around them, will help. Also, a tree with flowers or fruit may need watered more often. Make sure your pot has drainage holes, too, because no plant likes soggy feet.

Check to see if it's time to water by sticking a finger about 1 ½ inches into the soil. If the soil feels dry, give it a drink. However, if soil sticks to your fingers, wait a day or two and test again. After you water, dump out any standing water in the saucer beneath the pot.

Are Citrus Trees Toxic to Pets?

If you have a cat or dog who likes to nosh on your houseplants, it's best to keep these plants out of reach. The fruit is edible, but pets who ingest the skin or foliage may experience tummy upset, as well as dermatitis due to the essential oils, according to the ASPCA.

Why is My Indoor Citrus Tree Dropping Flowers or Fruit?

"This is normal," says Trejo. "Trees are smart and know what they can support." Take a close look; teeny fruit may be just behind. Most citrus trees will produce a lot of flowers, which become fruit, but they'll only hold onto about 25 percent of the fruit. It's nothing to worry about, especially if your tree looks green and lush. If individual pieces of fruit start to weigh down branches, support them with an overturned nursery pot or stacked books.

Can I Take an Indoor Citrus Tree Outside for Summer?

It's not necessary, but citrus trees do love being outside, especially during the cooler temperatures of spring and fall. Wait until it's no longer getting below 40 degrees at night before bringing them out. Gradually acclimate your tree to full sun so it doesn't get scorched, by leaving it out for a few hours, then moving it into shade, then finally working up to full sun conditions.

Before temperatures dip into the 40s and you need to bring it indoors for the winter, treat it with an insecticidal soap to make sure there are no hitchhiking bugs. Citrus trees are temperamental when you change their locations, so don't be surprised if it sheds some leaves once indoors because it's stressed. It typically will bounce back within about two weeks if you're giving it ample light and watering correctly. The growth does slow down indoors in winter, but it's still a lovely houseplant to enjoy year-round with the fun benefit of edible fruit.