GROWING CITRUS TREES
A citrus fruit is a tart, edible fruit produced by a citrus bearing tree (Citrus species). Citrus trees are grown in the Middle East as well as tropical and sub-tropical environments with warm winters and long growing seasons. Citrus have been cultivated by humans for thousands of years. There are several species and named varieties of Citrus, so it is important to choose one that is right for your area and taste preferences.
CHOOSING A VARIETY
Our citrus trees are grafted on to dwarfing rootstocks, and can be maintained at 3-10‘tall and wide, depending on variety and whether they are grown in the ground or in a pot.
Citrus are self-fertile, so do not require a different variety as a pollenizer to produce fruit.
Fruit ripen late fall to early winter depending on your location and variety. Meyer Lemon, if kept above 50°F, will produce multiple flushes of fruit throughout the year.
USDA HARDINESS ZONE
Citrus are hardy to USDA zones 9-11. This rating tells you the minimum winter temperature the plants typically survive when properly hardened off. On our web site you will find a USDA Hardiness Maps which provides information on the average minimum winter temperature in your location, by zip code.
Many plants native to locations that have cold winters have a Chill Hour requirement to ensure uniform waking up of flower and leaf buds in the spring. The chill hour requirement of plants varies by species, by cultivar, and sometimes by the level of dormancy achieved.
WHERE TO PLANT YOUR TREE
Citrus need to be planted where they receive at least 8 hours of direct sunlight measured in early summer (late June to early August). Sufficient sun exposure triggers the initiation of new flower buds for the next growing season, without which there will be no fruit. Fruit ripening and flavor development are also benefited by the carbohydrate production stimulated by the sun, as well as it’s heat.
Citrus prefer a sandy well drained soil that is moderately rich with a pH around 5.5-6.5. Improve your soil where you intend to plant by mixing an inch or two of plant based organic matter (manures are best for vegetable gardens), peat, or coconut coir into an area 1 1/2 to 2 times the diameter of the needed planting hole and up to a foot deep. A 2-4” deep layer of mulch (straw, leaves, or wood chips) applied after planting will continue to improve the soil.
Allow sufficient space for both the top of the tree and it’s roots when selecting the planting location. Refer to size descriptions for each variety, keeping in mind these are generally managed or pruned sizes, not maximum potential sizes. If you are planting an orchard be sure to include enough space between rows for transporting supplies in and fruit out.
GROWING IN CONTAINERS
In many parts of North America many forms of citrus cannot be cultivated outdoors without a greenhouse so many homeowners choose to keep their citrus in pots that can be taken indoors. Most citrus cannot survive temperatures below 25 degrees Fahrenheit.
To grow a Citrus tree in a pot you need a final container size of at least 10-20 gallons. Trees will grow larger in a larger container, but make sure you have the ability and tools to move the pots heavy weight. It is important for the establishment of the root system to gradually increase the size of the container over several years, rather than go from small directly to very large.
Do not use soil from your garden in the pot, instead use an acidic potting soil mix with some added sand For larger pots use a potting mix that has larger particles in addition to the smaller.
Citrus plants are also sensitive to drafts and sudden changes of environment (temperature, humidity, or sun intensity) which can cause them to lose their leaves. When moving indoors or out make the change gradually. If growing indoors, set the pot in a sunny window so it gets bright sunlight, or use grow lights. In an indoor environment citrus (and most plants) can rapidly develop severe insect infestations due to the absence of the natural predators that would otherwise keep these pests under control.
Citrus need lots of oxygen in the root zone, allow the soil to get quite dry between watering. Let the container dry until the soil is dry to the touch 3-4 inches down (more deep with deeper pots) and the container is lighter in weight. Add water until it comes out the bottom of the pot to ensure you fully saturate the container, then allow to dry again. Shoot tips and stems turning a wet brown color indicate the soil is staying too wet.