Freshly picked, home-grown citrus isn't a luxury reserved only for the picturesque gardens in the warm and sunny climate of the Mediterranean. Short on garden space? Growing citrus in containers can deliver you lemons even indoors. All it takes is some simple citrus basics, a little human ingenuity and you're on your way to growing your very own fruits.
Citrus plants grown in containers do best in porous pots that dry out fairly quickly since the roots do not like to remain wet for long. Make sure you remove your citrus from the plastic containers they come in when purchased as the heat from the summer sun and can cause the roots to burn.
Envious images of potted citrus can steer you toward big pots, but starting small and steady will win this race. Extra soil around trees complicates moisture control, so work your way up in pot size as trees grow. For small trees, a 30-cm diameter container is perfect for starters. Mature trees need pots double that width and at least 50 cm deep. This gives roots growing room and prevents tippy, top-heavy trees.
Be sure that whatever container you use has plenty of drainage holes so that water drains away freely. It is prudent to raise any container off the ground on "pot feet" to facilitate drainage and ensure good air circulation.
The soil should be sterilized, gritty, and free-draining. Some of the soil mixes especially formulated for containers work well; if they seem to hold too much moisture, add sand or gravel to the mix. Water carefully, as overwatering is a common mistake, you may feel you’re doing the plant a favour, but this smothering of love may lead to the drowning death of the plant.
Most citrus plants like to partially dry out (the top Five centimeters of soil should feel dry) before receiving more water. These plants are quite greedy and require regular feeding to do well. If you are repotting a plant, incorporate some timed-release fertilizer into the soil at planting time. Also, select a liquid fertilizer that is high in nitrogen and apply this approximately every other week.
Standard citrus trees grow too big for indoors, but dwarf varieties are grafted onto special roots that limit their size and speed up fruiting. Growing them in containers keeps them smaller, too. If you're new to growing citrus, start with dwarf types known to flourish and fruit well indoors. Easy-to-grow favourites, such as Meyer lemon, Key limes, Kumquats and Calamondin oranges, fit the bill.
When bringing pots in from outside before a frost, giving them a nice warm, slightly soapy wash will help to remove dust and any hidden pests, like a good wash should. They will also benefit from daily spritzing with plain water throughout the winter months to help raise the humidity level. When moving citrus from one area to another, do it gradually. Temperature fluctuations will stress the plant and can cause bud and/or fruit drop.