Adding a citrus tree to your home may seem a bit daunting, but they are actually quite easy to care for. When purchasing your citrus it’s important to keep in mind that it may take some time before they bear fruit,. This all can depend on the age of the tree and when it was grafted. Lemons and limes can take 5 to 7 years, while grapefruit, mandarins, and oranges can take up to 9 plus years. Depending on what size you are looking for, and how much you are willing to pay, you can find some that will bloom within the first year. Speaking of size, they are often sold in a manageable 3 gallon pot as a dwarf bush type or you can buy them in an actual tree form.
Just keep in mind citrus have the potential to grow 20 ft tall when planted in the ground and dwarf types, when planted in containers, can be kept to 3-5 ft tall. In general, Citrus trees prefer full sun in outdoor locations, or south facing window with lots of bright natural light. At least 8 hours of sunlight, as well as high humidity, 30% to 60%, are required for optimum growth and development. Optimum temperatures for fruit production are between 65°F and 85°F. Most citrus trees can tolerate cooler temperatures, down to around 50°F; however for some, even as low as 35°F. When it comes to winter care and temperatures drop below 25 °F, especially for extended periods of time, this can cause significant damage to citrus trees. During these cold periods, they will need to be moved into a protected area. Maintain the temperature between 55 °F and 65 °F.
Take in consideration the type of container that you will be planting in, make sure it has plenty of drainage holes and isn’t too heavy to move when it starts to get cold. Once temperatures are consistently over 50⁰F citrus can be moved back outside. Slowly acclimate them over a one to two week period. Otherwise you run the risk of sun burning your plant. When it comes to planting your citrus plant, it is just like any other tree you would plant in your yard. Make sure the root flare is above the soil line when planting; this will allow oxygen to get to the roots and prevent crown rot.
As for your potting mix, avoid using native soil. Think about using a slightly acid, well-drained potting medium, such as cactus mix. Repot your citrus every 2-3 years. Due to this sandy mix, you will have to water your citrus often throughout the summer, especially during the peak of the summer heat you will need to water every day. Before watering check, to see if there is any moisture in the top 2-3 inches of soil. During the winter reduce watering, as over -watering can lead to root rot. The soil should always be moist but never soggy. Because of the frequent watering in the summer citrus can experience nutrient loss.
Make sure to fertilize throughout the active growing season. April-September use a fertilizer for acid loving plants. Yellowing leaves may be a sign for a need of more fertilizer. If we take care of our citrus plants we want to be reward with fruit, right? The final thing we need to consider is pollination. Almost all citrus are self -pollinated, except for tangerines they need cross pollination. The fragrant flowers, which is worth having a citrus even if you never get fruit off of them, will attract honey and bumble bees to help pollinate. If you plan to always keep your citrus inside and are worried about pollination, when it’s flowering make sure to give your flowers a little flick to help spread the pollen around between flowers. Flower production is induced when the temperatures drop below 68⁰F.
Depending on variety, most citrus trees bloom in spring to set fruit that are ready to harvest in fall and winter. Others may flower and fruit off and on year-round, especially lemons and limes. Potted trees often set much more fruit than the tree can support, so fruit drop is very common. The time from blossom to fruit harvest varies by type and variety.
In general, most lemons and limes ripen in six to nine months. Citrus fruits ripen only on the tree, but can remain on the tree in good condition long after they are mature. Citrus have few pest issues; scale, mealybugs, aphids and spider mites are the common ones. Washing and wiping the leaves can help deter these insect pest; as well as insecticidal soaps and synthetic insecticides.
Submitted by: Jessica Bessin, Agent for Horticulture, Mercer Co. Cooperative Extension
Source: Andrew Jeffers, Clemson Extension