|I just purchased a dwarf lemon tree. I live in Northern New Jersey. When will it be safe to plant tree outdoors in full sun?|
|Citrus tress will not survive your winter weather outdoors, but you can grow the tree in a container, moving it indoors in the autumn and taking it back outdoors in the spring time. Citrus foliage can adapt to the relatively low light levels typical of our homes. However, if flowers and fruit are what you're after, you'll need to give the plants as much light as possible. If natural light is inadequate, you can supplement with artificial lights. A combination of cool white and warm white florescent lights placed close to the plants will help, as will the special "grow lights" that emit the wavelengths of light most important for plant growth.
Relative humidity is generally too low in the typical home, especially during the winter heating season. Running a humidifier will increase both plant and people comfort. Pebble trays with water evaporating from the surface also can be helpful.
Soil, water and fertilizer needs of citrus are similar to other houseplants. A good-quality potting soil mix with blooming-houseplant food applied according to label directions should be sufficient. Water thoroughly at intervals that allow the soil to dry just a little between waterings.
Citrus flowering is dependent on the particular species of plant, as well as environmental conditions. Generally, best success with flowering is achieved by moving the plant outdoors to a protected, partially sunny location after all danger of frost is past. Similarly, the plant will need to be brought back indoors at the end of summer, before temperatures dip below 50 F. However, unless the plants are gradually exposed to these drastic changes of environment, they will often respond by dropping many leaves and, possibly, flowers and young fruit.
If citrus is kept indoors year-round, the plants will likely need a bit of pollination assistance when they do flower. Use an artist's paintbrush or cotton swab to transfer pollen from one flower to another.
Take your tree outdoors during the summer months and it should live a long and happy life.