Lobelia Cascade Mix

Climate

• While "Cascade Mix" lobelias are perennial plants, they are hardy only in U.S. Department of Agriculture plant hardiness zones 10 and 11. They are grown as annuals in all other climates. The plants usually decline during the summer, however, in hot, humid climates. If this happens, trim off the sickly stems. This will encourage the plants to produce new growth and bloom again when temperatures cool down.

Containers, Potting Mix and Sunlight

• "Cascade Mix" is ideal for hanging planters, window boxes and other containers that let the stems hang down over the sides. Use containers that have drainage holes in the bottom so excess water will quickly drain out. These plants do not do well in slow-draining, soggy soil. Plant them in peat-based potting mix that also contains perlite and course sand for improved drainage. Place lobelia where it will be exposed to at least four hours of direct sunlight each day.

Water and Fertilizer

• Keep the soil uniformly moist. Water your lobelia two to four times per week, pouring 1/2 to 1 gallon of water over the soil until it begins to run out of the bottom of the container. Fertilize plants every two weeks from spring to fall. Use water-soluble houseplant fertilizer as it is formulated for plants grown in containers. Use fertilizer with a ratio of 10-10-10 in the spring and early summer then switch to 0-10-10 fertilizer at mid-summer. The common dilution rate is 1 teaspoon per gallon of water but it's best to follow the manufacturer’s recommended dilution rate.

Starting from Seed

• Lobelia "Cascade Mix" can be grown from seed. The seeds should be started indoors, two to three months before the last spring frost, in a mixture of potting soil, perlite and sphagnum peat moss combined in equal amounts. Do not cover the seeds with germinating mix. They require exposure to light in order to germinate. The soil must kept moist at all times. Temperatures of 55 degrees Fahrenheit at night and 72 degrees Fahrenheit during the day will result in faster germination. The seeds usually germinate within two to three weeks.