Caring For Indoor Citrus Trees

-Pam Scott-

Bringing tropical greenery into a room softens corners, adding an inviting warmth to most spaces. A windowsill full of blooming African violets, wintered over annuals, forced spring bulbs, scented geraniums, or fragrant culinary herbs will certainly brighten your spirits on a cold bleak day. The scents and colors of an indoor garden can remind us that the warmth and light that we crave during winter will once again be ours. One of the most rewarding families of plants to incorporate into your home is citrus. You can enjoy the lush foliage, fragrances, and fruits of lemons, limes, oranges, grapefruits, kumquats and other more exotic fruits with minimal effort.

Citrus plants need 6-8 hours of bright light, high humidity, good nitrogen-rich nutrients, and insect prevention to thrive. A south or west window will provide the perfect light for most citrus trees. If you can’t provide strong natural light for your citrus, however, you can supplement a shadier window with a full spectrum lighting set up.                                                                

You can summer over your citrus trees outdoors when temperatures are consistently above 50 degrees F, bringing them in again just before night temperatures fall into the 40’s. When transferring citrus outside you will want to provide some shade protection against hot midday direct sun. Move your plants gradually from part shade to full sun to avoid burning the leaves.

Your citrus trees will most likely flower (making your house smell GREAT), setting fruit in the spring and summer, which will ripen in 6-8 months. They will be ready to harvest and enjoy in late winter or early spring. Most citrus trees are self-pollinating, with both male and female reproductive parts contained in each flower. The exception to this is some varieties of tangerine that are self-sterile and need another tangerine variety for pollination.

Citrus trees will benefit from being outdoors for the summer, as they enjoy the high humidity that most air conditioned houses don’t provide. Keeping humidity high for your citrus is especially important indoors in the winter. Misting your plants once or twice a day during the cold months will keep the foliage lush and help to ward off insects.

You will want to keep your citrus moderately moist but not soggy. Your plants should be potted in a well draining soil; if you find your soil is too dense, add some perlite to the mix. Over-watering will rot the roots – so don’t let your soil get soggy; under-watering will result in leaf and fruit drop – so don’t let your soil totally dry out, like with a cactus or succulent plant. When your citrus is outdoors, be sure the pots are draining well and the plants are not sitting in water after rainfall.

When repotting a citrus tree, which can be done every 1-2 years, only up-pot one size bigger than the current pot. Too big a pot will provide too much moisture in the soil for the root ball to absorb, this will contribute to root rot. Be aware of the changes in humidity in your house – when air conditioning or heat is in use, the air can become suddenly dry, affecting your watering needs.

Citrus trees are heavy nitrogen feeders. A consistent regimen of fertilizing your citrus plants will keep them happy and productive. They will enjoy a granular top dressing fertilizer for acid loving plants such as the Happy Frog Citrus and Avacado Fertilizer, Marine Cuisine Fertilizer, or the Happy Frog Acid Loving Fertilizer. All three of these products provide slow-release, primary plant nutrients, as well as a full range of important micronutrients. Be aware that if your citrus has just come from the grower it has been provided with slow release nutrients already. Ask your Fifth Season associate when the best time would be to begin a nutrient regimen to avoid over-fertilizing your newly-acquired tree.

Like most greenery, citrus plants can attract bugs. This seems to be more of an issue when the plants are indoors than when they are outdoors. Plants summering outdoors enjoy the protection of natural predators and rainfall to rid the plants of unwanted pests, although the occasional slug may decide to make a meal of their foliage. Sluggo Plus is an excellent product to sprinkle around the base of your plants to prevent such pests.

Indoors, your citrus plants may attract spider mites, scale, and, on occasion, mealybugs and aphids. I have found that alternate treatments of Safer insecticidal soap and Horticultural oil applied every other week in fall and winter plus daily misting will keep my plants pest-free.

Prune your citrus trees at any time to maintain shape. Many kinds of lemons and limes are dwarf tree varieties, naturally maintaining a short, shrubby growth. Some fruit trees have been grafted; always prune the growth coming from below the graft, as it will detract from the health and fruit-bearing capacity of your tree.

Your citrus trees can provide you with years of cooking fun, providing fruit for lemon curd, lemon crepes, preserved lemons, marmalades, bitters, key lime pies, sorbets, and countless other desserts, condiments, and cocktail fixings.

Stop by Fifth Season Gardening for all your tropical plants, organic soils, nutrients, lighting needs, and advice to make your indoor gardens flourish year-round!