Californians and Floridians are blessed with fragrant citrus trees in their backyards that bloom all spring and seem to be in season all year. For the rest of the country, where climates aren't conducive to growing citrus outdoors through all four seasons, you have to get a little crafty if you want homegrown Key limes for your cervezas.
The trick is to grow citrus in a container that you can keep outside from spring to fall, but move inside before the first freeze arrives. Aside from that, container citrus is very easy to grow. The hardest part is choosing your favorite cultivar among all the different types of citrus, and there's quite a lot in this category: oranges, mandarins, tangerines, grapefruits, lemons, and limes, not to mention the whimsical array of hybrids like tangelos and mandarinquats.
Selecting a Tree
A citrus tree will only grow to the size of the container it's planted in, so any type of citrus will technically work. But, a dwarf or semi-dwarf variety does best in small quarters and requires less maintenance than a full-sized citrus variety.
Popular choices for containers include kumquat, Trovita orange, Calamondin orange, Oroblanco grapefruit, Bearss lime, kaffir (makrut) lime, Mexican lime, Improved Meyer lemon, and Buddha's Hand citron.
Selecting a Container
As a general rule of thumb, a citrus tree should be repotted into a container that's at least twice as large as the nursery pot it came in. For a one-year-old tree, you can start with an 8-inch-diameter container. For a two- to three-year-old tree, choose a 10- to 14-inch-diameter container. Eventually, you'll want to move to a 16- to 20-inch-diameter container (or half-whiskey barrel) for long-term growth. However, it's best to start with the smallest container that will suffice for your young tree, as it'll be easier to maintain moisture the first few years.
With any container, depth is important as it will support a strong root system and keep your tree from toppling over as it grows. If you have to haul it a long distance across the yard and inside the house every fall, consider a lightweight plastic pot (instead of clay or wood) for ease of moving.
Light and Temperature Needs
Citrus trees prefer sun, warmth, and humidity. Place your tree in a location that receives 8 to 12 hours of sunlight per day and maintains a daily temperature between 55°F and 85°F, around 65°F is ideal. When the night temperatures starts to dip into the upper 40s or when the day temperatures no longer exceed 50°F in fall, move your tree to a sunny but sheltered location indoors to protect against frost.
How to Plant Your Own Citrus Tree
- Dwarf citrus tree
- Container with sufficient drainage holes
- Miracle-Gro Cactus, Palm & Citrus Potting Mix
- Miracle-Gro Shake 'n Feed All Purpose Plant Food
- Fill the container about halfway with Miracle-Gro Cactus, Palm & Citrus Potting Mix.
- Remove your tree from the nursery pot and gently loosen the bottom of the root ball. Trim off any dead roots and detangle any circling roots so their growth won't be impeded in their new environment.
- Set the tree inside the container to check the planting depth; the top of the root ball should fall about 3 inches below the rim of the container. Backfill the container with more potting mix until the roots are just below the surface.
- Water slowly and thoroughly, making sure the potting mix is well saturated and the water is freely draining out the bottom.
- Mulch the container with a 2-inch layer of mulch, keeping it a couple of inches away from the trunk. Gently tamp down the mulch to smooth the surface.
Caring For Your Citrus Tree
Water deeply every 5 to 7 days, depending on the size of the container. In peak summer or during periods of extreme heat, trees may need more frequent watering (sometimes daily) if they're in direct sun all day. The soil should stay consistently moist but not waterlogged; make sure your container never sits in a pool of standing water. To determine how thirsty your tree is, use a moisture meter or the finger test: water when the first 2 inches of potting mix feels dry. Curled leaves are a sign that your tree needs more water.
Start feeding your tree about a month after planting with Miracle-Gro Shake 'n Feed Continuous Release All Purpose Plant Food. Sprinkle evenly over the surface as instructed on the package, being careful to avoid contact with the trunk. Work it into the top 1 to 3 inches of potting mix.
Prune any suckers (new shoots) that appear below the graft. You can also prune any errant branches in spring to maintain balance or a desired shape.
Spray the foliage periodically with water in winter to keep humidity levels high. An occasional shower when the tree is outside also helps reduce the risk of pests.