How to Grow a Zinnia Flower
- 1). Prepare the soil where you intend to grow zinnia plants by using a garden shovel to work 2 to 3 inches of organic material, like dry leaves or grass clippings, into the soil, to a depth of 6 to 8 inches. Zinnias prefer to grow in sunny locations, in soil that is loamy and well draining. Adding organic matter will help keep the soil loose and drain better.
- 2). Sow the zinnia seeds after the last threat of frost directly onto the prepared soil area, then lightly cover the seeds with 1/4 inch of soil. Water the planted area and keep the soil moist, not soggy, while the seeds germinate for the following two to four weeks. As the zinnia seedlings grow, you can begin watering the plants on a regular schedule, the same as the rest of your landscape or garden.
- 3). Thin the zinnia seedlings when they are 2 to 3 inches tall, spacing the plants 6 to 8 inches apart, leaving more space for tall-growing zinnia varieties.
- 4). Fertilize the zinnia seedlings when the plants are 4 inches tall with a 5-10-5 formulated liquid fertilizer that you mix at one-quarter strength. After this initial feeding, do not fertilize the zinnia plants again until the plant is budding with flowers, and then apply the 5-10-5 liquid fertilizer according to the directions monthly.
- 5). Clip the spent and dying flower heads from the zinnia plants throughout the growing season to extend the blooming time. Use garden snips or shears to cut the dead flowers just above a leaf joint on the stem. This will force the plant to grow a new bud stem and flower and make a fuller looking zinnia plant..
