How to Grow Watermelon Coleus

Locate a shady or partially sunny planting area that has consistently moist soil in which to plant your watermelon coleus.

Dig a hole that is the same depth and width as the pot that the watermelon coleus is in. Turn the pot upside down and gently slide the root ball out. Insert the coleus roots into the hole and ensure that the top of the root ball is flush with the soil surface. Back-fill the planting hole completely with soil.

Plant additional watermelon coleus, if desired, spacing them at least 12 to 18 inches apart.

Water the soil under your watermelon coleus as often as required to keep the top of it constantly moist but not wet. The top of the soil should always feel like a damp kitchen sponge.

Read the mixing instructions on a bottle of water-soluble liquid plant fertilizer then add the suggested amount to a large pitcher. Fill the pitcher with twice the amount of water instructed on the bottle. Apply the fertilizer to the soil once per month from spring through fall or every two weeks for coleus in containers.

Pinch the tips of each stem back by approximately 1/2-inch every month to two months to encourage new stems instead of vertical growth. This technique produces a bushier plant with more leaves.

Watch for the development of central flower stalks, which typically contain light purple flowers. Cut them back to the center of the plant with hand pruners as soon as they emerge. This lengthens the life of the coleus and produces more foliage.