Growing Citrus Indoors
The University of Minnesota explains that growing citrus plants indoors works best at 65 degrees during the day and dropping five to ten degrees at night. Citrus likes to be planted in soil that has a fair amount of organic matter. You will also need to periodically wash the leaves as they like to be kept clean. Citrus make a great houseplant but you may want to accept that getting a fruit on them may be just an added bonus in our climate.
Citrus like to have sun for at least part of the day. During the summer, these plants CAN go outside. Take advantage of the extra sun and warmth! Once they are used to being outside, make sure they get plenty of direct light. By the end of the summer, you need to get them used to lower light by keeping them in a shady spot about a week before you bring them back inside.
Citrus like acidic soil so using peat moss in the potting mix will help keep the pH down. Citrus should only be fertilized April through August or September.