A true annual is a plant that completes its life cycle in one year. This means it goes from seed to seed and then dies off, during the course of one growing season. The whole mission of an annual is to produce seed and propagate. That’s why deadheading or removing spent flowers before the seed matures, produces more flowers and therefore more potential seed.
1. Planting and spacing: Plant transplants closely so they fill in quickly. Usually, the tag will say to plant 8 to 12 inches apart, so pick 8 inches for a great show of flowers more quickly. I actually take a ruler into the garden, or measure off the spacing with my trowel. If the plants are a bit pot-bound (roots circling around), cut an X into the bottom with a knife or use your fingers to tease them apart so they make better contact with soil.
2. Watering: Annuals need water to thrive. Water them deeply two to three times a week after planting. The moist soil will encourage good growth. For the best show of color all summer, don’t let up on the watering.
3. Feed your plants: Once a week, feed your plants with a balanced all-purpose 20-20-20 fertilizer that you mix with water. You’ll find traditional or organic fertilizers – either will do the job. One good organic is fish emulsion, which I like to mix together with a kelp-based fertilizer. Your annuals will grow even better if you mix some compost or manure into your soil before you plant.