Garden Variety: Growing your own citrus indoors

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Most homes are already at ideal temperatures for growing citrus plants.

The freshness and availability of citrus fruit in winter months inspires many gardeners to consider growing their own lemons, oranges and other fruit. In Kansas, citrus production is challenging but doable with a sunny window, a little space, and a bit of gardening know-how.

Citrus plants are tropical and require winter protection in regions where temperatures fall to freezing or near-freezing. Greenhouses, glasshouses, hoophouses and similar structures are ideal for citrus in cold climates but are costly to heat.

Most homes are already heated to ideal temperatures for citrus. Growing citrus plants in your home is an ideal option if adequate light is available or can be supplemented with grow lights. Lemons, limes, oranges, grapefruits and kumquats are popular options for container-grown home production. Citrus plants generally perform best when moved outdoors during summer months but in some cases may be kept indoors year-round,

When selecting plants, look for dwarf varieties suitable for growing in containers. Local garden centers and plant shops with knowledgeable staff are good resources on which varieties perform best in this setting.

Drainage and good watering practices are keys to keeping citrus alive and healthy. Use terra cotta pots if possible. Glazed ceramic and plastic containers retain moisture longer than terra cotta and make some plants, including citrus, prone to root rot.

Set citrus plants in a sunny window where they receive at least 6 hours of direct sunlight per day, or use grow lights to provide adequate light. When moved outdoors during the summer months, they will also need 6 hours or more of full sun. Move plants outdoors when nighttime temperatures consistently stay over 60 degrees.

Let the potting mix completely dry between waterings. Use a soil moisture meter to confirm moisture levels below the soil surface if needed.

Avoid fertilizing in fall and winter. Use light, regular applications of fertilizer in spring and early summer when plants are actively growing.

Let the plants get pot-bound, meaning the roots completely fill the container in which they are growing. Citrus plants seem to like this condition, and growers claim the plants produce more fruit this way. When plants need repotting because the top is too heavy for the container and root system, use a pot only slightly larger.

When potting or repotting, use a high-quality all-purpose potting mix or one that is designed for citrus, or blend your own. Citrus plants prefer slightly acidic soil, or a pH around 6.0. Get a pH meter to check the pH of the mix and make adjustments when needed.

If pruning is needed, do it right after plants have produced fruit to avoid diminishing production later. Prune to redirect unruly branches or provide minimal shaping, but avoid overpruning.

Meyer lemons, oranges, grapefruits and kumquats are usually harvestable through the winter, starting in mid-November (depending on variety). Limes and other varieties of lemons may produce fruit at other times of year.

Citrus plants can be hosts for many insect pests, including mealybugs, scale insects and spider mites. Monitor plants closely for signs of pests and control them as soon as possible if found.

Citrus plants are also prone to a condition known as iron chlorosis, when plants have difficulty taking up iron. This is especially common when transitioning plants from outdoor settings to indoors. Use foliar iron chelate to correct the issue.

— Jennifer Smith works in regulatory horticulture and has worked as a horticulturist for various government entities. She has experience in landscape design and maintenance and as an educator.