Rainbow Mixture Coleus Seeds

Coleus flower seeds should be started indoors 6-8 weeks before the last frost date. This will give the young seedlings a head start, and you will get first flowers in June. Plant the seeds on the surface or not deeper than ¼ inch. These seeds are very small and planting them deep will quickly stop the germination rate. You may add a small amount of dry sand to the seeds to evenly distribute them in a tray. The soil should be kept at 70-75°F and under artificial lighting. Seeds will not germinate in the dark. Germination time for Coleus plant seeds take 7-14 days.

The ideal location is part shade to part sun. Too much sun, especially in the afternoon, causes color loss and stresses the plant out; too little sun causes long leggy stalks and dull leaves. Choose loose, fertile, and well-drained soil. Add organic compost to the soil prior to planting instead of relying on fertilizer to compensate for poor structure. Watering should be regular; Coleus has a tendency to wilt terribly if it lacks water. However, repeated drought stress can reduce the life of the plant significantly. Never let pots sit in standing water, as it causes root rot.

Pinch the center stem when they're about 6 inches tall. Just snip the top inch or two to stimulate the side branching and keep the plant bushy, not tall and floppy. Do this once, and you won't have to fight the shape all season. Deadhead the flower spikes as they appear to encourage continuous flowering. Fertilize monthly with a balanced slow-release granular fertilizer, and liquid fertilizer every few weeks during the summer. In the fall, pot up a few favorites before frost and overwinter them indoors in bright filtered light — you'll have free cuttings by spring.