The What and How of Summer Fertilizing

We know plants are alive, and we tend carefully to their needs. We fret over their health. “Are my daylilies getting enough sun? Better water my delphinium bed; it’s looking thirsty!” But we don’t stop to consider the soil’s health, which is the foundation of a prosperous garden.

But what is healthy soil?

A common misconception is that soil is just dirt, a static growing medium, but actually soil teems with life. It’s an ecosystem filled with bacteria, fungi and other microbes. These organisms break down organic matter in the soil and release nutrients to plants. So healthy soil is the right mix of these components, a balanced ecosystem that has the continued capacity to sustain plants, animals and humans.

Enlightened gardeners shift their thinking and understand that they are feeding the soil first, not the plants. Healthy soil yields healthy plants.

Now, I apply fertilizer at planting. Generally, you’ll need to reapply a fertilizer in spring and continue to fertilize heavy feeders as the season progresses. Here are my tips:

Fertilizing Annuals

Annuals complete their cycle in one season and are often grown for their dramatic flowers. They start fresh each spring and die in fall, meaning they have to expend tremendous energy during the short season to produce stems and leaves. They need more fertilizer than perennials, which have the advantage of starting over each season from a robust root system. Feed the soil with a granular fertilizer at the beginning of the season and every ten days with a water soluble product for a spectacular display.

Fertilizing Perennials

Because they are starting with a good root infrastructure, perennials have a leg up on annuals, but fertilizer is still a must. Apply fertilizer to the soil around these versatile plants at spring’s beginning to ensure a proper exhibit.

Fertilizing Shrubs

Woody plants have trunks and branches that live from season to season, a big head start. Fertilize when you first plant and again at the beginning of the growing season.

A caution, don’t fertilize woody plants late in the growing season. Since the response to fertilizing is growth, new growth needs time to harden so it will survive winters.

Fertilizing Vegetables

Most vegetables grow quickly, and many vegetable garden favorites are high producing, heavy feeders, meaning they quickly deplete nutrients from the soil. Feed the soil throughout the season, according to package directions.