Geraniums are tender perennials that cannot survive the freezing temperatures of winter. But they do not have to be replaced each year if you choose to grow them in containers. Flower pots full of these bright flowers with their lush green foliage are attractive when displayed on patios, from hanging baskets or indoors to grow over winter. Potted geraniums can also be grown indoors year-round, as long as they receive enough sunlight from a nearby window.
Fill a 10- to 12-inch diameter flower pot with a moist potting soil, leaving a 1 inch of space between the top of the soil and the rim of the pot.
Tap the sides of the nursery pot the geranium is in to loosen the soil and root ball. Lift the plant out of the nursery pot, then place it in the permanent pot at the same depth it was in the nursery pot.
Water the geranium after transplanting until the excess moisture drains out the bottom. If you're using a drip tray, empty any excess water.
Place the geranium in a window where it will receive at least six to eight hours of sunlight. If you're growing it outside, place it in a location that receives full sun. In the winter months, if sufficient light is unavailable, set the geranium 12 inches below a grow light or 40-watt cool fluorescent bulb for 16 hours a day.
Check the moisture in the soil daily by sticking your finger into the soil. Water only when the top 4 to 6 inches of soil begins to feel dry. Water from the top until the excess drains into the drip tray, then empty the drip tray. Constantly wet roots will lead to root rot.
Fertilize the geranium every other month throughout the spring and summer with a soluble, slow-release balanced plant food. Follow label instructions for exact application amounts and methods.