How to use the plants
I. indica blooms in one year from seed, but you can also start with young plants. It's a perennial (to 30 feet tall) in Sunset climate zones 8, 9, and 12-24, annual elsewhere (in frost-prone areas, it dies to the ground in winter). Needs sturdy support; use it to cover a bank, fence, trellis, or unsightly structure (like a chain-link fence).
I. tricolor is an annual (to about 15 feet tall) and grows in all zones. Use it for quick color on arbors or trellises, or plant it in large containers; provide tall stakes or wire cylinders for it to climb. Plants reseed profusely; hoe out unwanted sprouts as soon as they appear.
For cut flowers, pick stems with buds in various stages of development; place them in a deep vase. The buds will open on consecutive days.