Begonias are summer bloomers that are grown from root sections called tubers, sometimes referred to as bulbs. These bright flowers come in a variety of colors, ranging from bright red and orange to a muted pink. Prized for their long flowering season, begonias prefer shady areas and do well in containers and hanging baskets outdoors. Start begonias in the spring after all frost danger has passed, or in early spring for container plants. Begonias prefer daytime temperatures from 70 to 80 degrees F to bloom, but will tolerate some cooler or warmer days.
Fill starting pots with vermiculite or build up outdoor beds to improve drainage by working 2 to 3 inches peat moss or compost into the soil. Choose an outdoor bed that is shaded with only indirect sunlight.
Find the hollow side of the tuber. Place the tuber in the soil or vermiculite with the hollow facing up. Cover in a thin coating of vermiculite. You should still be able to see some of the tuber through the covering. Space each tuber 8 to 12 inches apart.
Water the soil until it is moist but not soaking wet. Too much water will cause the begonia to rot. Take care not to get water in the hollow on the tuber.
Place the bulbs in a warm place to sprout, or plant them outdoors once daytime temperatures reach 70 degrees F. Use a heat mat indoors to help maintain soil temperature. Sprouting takes approximately two to four weeks.
Transplant potted begonias to well-draining, permanent containers when they reach 1 inch tall. Remove the tuber from the vermiculite mixture and place it in the potting soil of the full-size container. Pull enough soil over the tuber to just cover the top.
Water begonias regularly, letting the top layer of soil dry out between waterings.
Apply a balanced liquid fertilizer to containers and beds monthly during the growing season.