Citrus are one of those plants that I think are a must in the garden. They have beautiful dark green foliage all year, sensuously perfumed flowers at various times of the year and then produce fabulously colorful edible fruit. They really are the most perfect garden specimen. Citrus grow well in containers which gives you the ability to move them to different places in your landscape or your deck. Potted up citrus can be moved to protected areas to avoid freezes.
Like all other plants, citrus trees grown in containers plants need more watering than in ground plants because of their restricted root run and although citrus like a hot and sunny position, they also require good soil moisture levels to stay healthy and produce well.
You will need to feed your potted citrus: they are prone to micro nutrient deficiencies, which is exacerbated by the constant watering, so you need to ensure that you apply a fertilizer with a variety of trace elements especially iron manganese and zinc. For citrus in containers I like to apply the rule “A little often” In spring and early autumn I apply slow release organic pellets and then supplement this with regular liquid feeds from early spring through to late autumn. The type of liquid feed I use is dependent on the growth stage of the plant. When the plant is young, I use a high nitrogen ratio fertilizer to encourage plenty of growth which will develop into a strong branch structure. High nitrogen ratio fertilizers also discourage flower and fruiting which is necessary until the tree is large and strong enough to hold full sized fruit.
Kathy Finigan, My Productive Backyard