Citrus plants have very attractive, glossy dark green leaves and the scent of their flowers (and to a lesser degree) their foliage is absolutely incredible! There are several varieties of lemons, limes and grapefruits that make great indoor plants. But don't stop there. You can also grow dwarf kumquats, tangerines and oranges. Not all of them will bear fruits like you buy in the grocery store, but some do, especially lemons and limes. Others will bear smaller, intensely flavored fruits that can be used in special recipes.

The size of indoor citrus plants can vary greatly, so when selecting a citrus plant to grow as a patio or indoor plant, it is important to find out how large it will get. Most indoor gardeners are familiar with Calamondin orange, a compact dwarf orange variety that has fruits about the size of a quarter. It generally stays in the 2-3 foot range. Another popular indoor citrus is the Meyer lemon. It can get to be a large indoor plant, so be sure you have enough room. Meyer lemons can produce large, thin-skinned fruits with wonderful flavor. Even a dwarf lemon may grow as much as 8 feet tall.

To select a citrus for indoors, look for plants that are full of dark green glossy leaves. If the variety is grown as a standard, pick a plant with a strong, straight trunk. Whenever possible, select a plant that is just beginning to bloom so you can enjoy the fragrance right away. Handle citrus plants carefully. Many of them have thorns.

How much water do they need?
In summer, when they are outdoors, citrus trees need water almost daily. When grown indoors, their soil should be allowed to dry to the touch between watering. Do not allow them to stand in water after the pot has drained into the saucer.

Do they have any special temperature requirements?
They like slightly cooler temperatures than the average home. They like 50º to 55º at night and 68º during the day.

Do citrus need much humidity?
Citrus need high humidity, especially when blooming. Low humidity is often a reason for dropping blooms and fruit. Mist them daily, stand them on a pebble tray full of water or use a humidifier.

How much fertilizer do they require?
Citrus should be fed three times a year, early spring, early summer and late summer. They prefer an acid fertilizer applied no stronger than the recommended rate.

What type of soil do they prefer? A
potting soil designed for African violets suits them well. Just be sure it is well-drained.

When should I repot my citrus?
Repot annually into only slightly bigger pots. If they fail to bloom well, skip the repotting for a year or two. Being slightly crowded seems to encourage blooming.

Will they need any grooming?
Do not use leaf shine products on citrus. Their leaves will be damaged. Pruning tip growth at any season will keep the plant compact and bushy. Deadheading is not necessary as the blooms fall off as they fade and fruit will follow if the flower was pollinated. Indoors, you will have to pollinate the flowers by hand. Use a child's paintbrush to stroke the pollen-bearing stamens and then the pistil in the center of the bloom of each flower.

How are they propagated?
Take stem cuttings in late summer or early fall and root them in moist sand. When new growth doubles the size of the cutting, it can be potted up into the same kind of soil used for the mother plant and grown on the windowsill. Use fertilizer half strength until the plant is large enough to repot.

Why are the leaves yellowing and falling off?
The plant could be over watered. If you are sure this is not the case then your tap water could be the problem. Citrus plants are very intolerant of the salts that accumulate when they are watered with tap water. In addition to the yellowing leaves you will often see crusty accumulations of salts on the pot. The plants will decline and eventually die if the problem is not corrected. There are several ways to combat this problem: you can water them with distilled water, water from a dehumidifier, rainwater or melted snow. Another approach is to use tap water, but once a month to flush the plant with water that has 2 tablespoons of household vinegar (white or cider) to the gallon. Pour enough into the pot to run out the bottom, empty the saucer, then repeat twice more. This leaches out the salts.

Why are the leaves becoming dull and mottled?
Your plant might be under attack by sucking insects such as spider mites, white fly or scale. All of these can be safely controlled with insecticidal soap or horticultural oil if caught early. See Bachman's Information Sheet Indoor Insect and Disease Problems for more information.

Why doesn't my plant bloom?
There may not be enough light, it might be too warm or the pot may be too large. If you think it might be the latter, don't repot the plant until it has bloomed. You cannot correct the situation by putting it back into a smaller pot.