How to Grow Chianti Sunflowers

Choose a planting site for the Chianti sunflower with full sunlight and rich, well-drained soil. Remove all plant life in the area as well as any rocks, branches or debris.

Break up the soil to a depth of 6 inches or more using a mechanized tiller or hand garden tools. Amend sandy or clay soils with organic matter, such as rotted leaves, aged manure, peat moss and compost.

Dampen the soil and sow Chianti sunflower seeds 1 to 2 inches deep. Space the seeds one to two feet apart and keep the soil moist until seedlings emerge in one or two weeks. Thin to one sunflower plant every two feet when seedlings reach 3 to 6 inches.

Plant Chianti sunflower transplants at the same depth as the container. Space the plants two feet apart when planting rows and drench each plant to settle them in place.

Add a 1- to 3-inch layer of bark or leaf mulch around the plants but keep the mulch away from the Chianti sunflower's stem.

Supply water to the Chianti sunflowers at a rate of 1 inch per week during any dry periods throughout the growing season. Water the plants gradually and deeply with soaker hoses.

Apply a low-nitrogen fertilizer, such as 5-10-10, to the Chianti sunflowers. Reapply as instructed on the package throughout the growing season or use a slow-release formula that lasts several months.