Rainbow Mix Coleus Seeds

Coleus Rainbow Mix is a popular heirloom mixture that produces plants that are cultivated for their leaves rather than their flowers. Coleus grows to about a foot high with medium-sized painted leaves. This reliable blend will produce plants in splashy patterns of cream, yellow, green, purple, red, bronze and pink. Coleus Rainbow Mix grows well in full or partial shade, so it is an ideal candidate for shady borders, container gardening, hanging baskets or as an easy-to-care-for house plant.

GROWING INSTRUCTIONS

Coleus is an exceptionally unique plant that is cultivated outdoors and indoors. It displays symmetrical, multi-coloured leaves of varying sizes and shapes. Coleus does produce small flowers, but these are usually discarded to conserve energy for the decorative leaves. Although they’re tender tropical plants, coleus will grow well as an annual in a variety of places. The brilliant colours can add a touch of pizzazz to garden beds, landscapes, window boxes, containers and hanging baskets.

Just beware of coleus’ toxicity to pets.

Start seeds indoors eight to ten weeks before the last frost date. Have patience because seeds may take up to 21 days to germinate. But once sprouted, with a month of warm weather, young coleus can transform into a fully developed plant. Scatter seeds thinly over a flat filled with potting soil and cover lightly. Mist the soil well and cover the flat with plastic wrap to trap heat and moisture. Place the tray in a warm and bright spot and remove the plastic when seeds germinate.

Transplant seedlings into their own pots when they have two sets of true leaves. Keep them well-watered and under bright light until all danger of frost has passed. Give young coleus plants a period of hardening off to prepare for transplanting outdoors. Temperatures should reach and remain above 16 degrees before permanently moving the plants outside.

Coleus will do best in part-shade to full-shade. Abundant sunshine can burn leaves and fade colours. Filtered sun in the morning and shade in the afternoon is the ideal scenario. Coleus kept as houseplants get requisite light from indirect sunshine, but will need some direct sunlight during winter months.

To keep coleus happy and thriving all year long, plant it in loose, rich, well-drained soil that’s been amended with compost. Soil should stay moist but allowed to dry out a bit between waterings.

Coleus can be pruned to promote full, stocky plants. Pinch out the stalks below the flower buds when plants are about 15 cm tall. Coleus will thrive in hot and humid conditions and any touch of frost will kill it off. Bring plants inside or cover them on cold nights when temperatures drop to 10 degrees or lower. Cuttings for propagation can be taken from plants before winter rolls around. No matter how you grow your coleus, they’re certain to brighten up any space they occupy. 

QUICK FACTS

- Coleus was named by the botanist Karl Ludwig Blume in the mid-1800s, after finding coleus cultivated in the Dutch colony of Java, an island of today’s Indonesia.

- Coleus seeds will remain viable for 2 years if stored in a cool, dark place, ideally between 4 and 10⁰C. After that, the germination rate may start to go down.