Every home should have at least one citrus plant! Packed with vitamin C, citrus trees have shiny evergreen leaves, fragrant flowers, and attractive fruits that hang for months. Although it’s not so practical to grow large citrus trees outdoors in our climate, it is possible to enhance a sunny area in your home or on a patio with a containerized dwarf citrus plant. The fruits from a smaller citrus plant grown in a container are the same size as the fruits from a full-grown citrus tree, and the flavors are just as delicious!
Varieties & Selection
All types of citrus fruit is easily damaged by frost, but the leaves and wood of some plants are more cold-resistant. In general, limes are the least hardy, oranges are slightly hardier, and kumquats are the most hardy. Varieties that tend to do well in our area include:
Meyer lemons are rounder and sweeter than most lemons. Their thin skin is slightly orange (it’s actually a type of sour orange; not a true lemon!). Fruits usually develop during late winter or early spring, but indoors, they are unpredictable and can produce at any time. Fruit becomes sweeter as it hangs on the tree. Because of their thin skin, Meyer lemons don’t ship well and therefore, are not widely sold commercially.
TIP: Select sturdy, nursery-raised plants with only a few fruits or flowers; they have put more energy into a sturdy top and better root development.
Citrus plants do best in full sun or with at least 6–8 hours of direct sunlight daily. Lots of light will promote blooming. If kept indoors during winter months, it is best to keep under grow lights for 12 hours per day.
Water thoroughly until water drips from the holes in the bottom of the pot, and allow to get somewhat dry between watering (like any containerized plant). Soil should dry down about 2–3 inches between waterings. Never wait until the leaves wilt to water; the stress can cause developing fruit to drop, and prolonged drought causes leafdrop and may even kill the plant. In winter, water less and do not fertilize in order to accommodate the lower light levels.
Fertilize with organic acid fertilizer in spring and summer prior to the flush of new growth and again in late August. Fertilizers specifically for citrus plants include G&B Citrus & Fruit Tree Fertilizer and G&B Rhododendron, Azalea & Camellia Fertilizer. They are both organic, probiotic, people and pet safe, and feed for several months.
Pruning & Repotting
Dwarf citrus can grow 6–8 feet, but can be pruned at any time to keep the plant compact and bushy. If necessary, repot in early spring when you see signs of new growth (not yearly—about every 3 years). They prefer being root-bound to encourage blooming and reduce the possibility of root rot due to overwatering. If you don’t want to pot up to a larger container, treat as a bonsai: Remove plant from pot, trim some top growth and some roots, add fresh potting soil, such as G&B Palm, Cactus & Citrus Planting Mix or G&B Acid Planting Mix, and replant in the same size container.
Many folks who grow citrus in the Pacific Northwest keep them outdoors almost year-round. Citrus plants need cool temperatures in winter, but cannot tolerate much below freezing. To protect against winter conditions, move containerized plants close to the house and out of wind and rain; water as needed. If temperatures drop below 30°F, bring plants into a more protected area where temperatures are above freezing, like inside of a garage. Keep away from heat vents and fireplaces. They can lose their leaves in heat or with sudden changes in temperature, light, or humidity; this is a normal reaction—foliage will grow back when the environment stabilizes. It is safe to return plants outdoors when temperatures rise to 29°F or above.
In spring, when nighttime temperatures consistently reach 50°F, it’s time to keep your plants outside again (usually late April). Choose a site that gets morning sun with afternoon shade. As the plant acclimates to the sun, it can be gradually moved to a full sun location. In fall, when nighttime temperatures begin to drop below 50°F, bring your citrus indoors to a cool and bright location (usually late October). Citrus plants are hardy to Zone 9.
There are a few pests that are common to citrus plants, especially when kept indoors. Keep an eye out for aphids, spider mites, mealybugs, and scale. Look for honeydew as an indicator of insect problems. Prevention is best; inspect your plants often to catch any problems early and spray monthly with horticultural oil. Use insecticidal soap, neem oil, horticultural oil, or spinosad (ask one of our experts for a product suggestion) when pests are present.