How to Grow Astilbe Perennials

Astilbe plants grow well in a shade garden.

The astilbe is an flowering perennial that flourishes when planted in a wooded area or partially or fully shaded flower garden. Astilbe plants reach a height of 2 to 4 feet and produce feathery blossoms during the summer months of June and July. The plant is low maintenance and hardy to plant in USDA growing zones 4 through 8. The astilbe has no major insect or disease problems, but will turn brown when the water supply in inadequate.

Things You'll Need

• Organic compost
• Shovel
• Water
• Organic mulch
• Pruning clipper
• 5-10-5 fertilizer

Instructions

1. Select a planting area for the astilbe that has a nutrient rich and well-draining soil in a partially shaded garden bed. Astilbe plants grow best in partial shade but will grow in full sunlight if supplemental water is provided on a daily basis.

2. Mix 2 to 3 inches of organic compost into the soil to a depth of 6 to 8 inches. This will increase the nutrient content and moisture retention properties of the soil.

3. Dig a planting hole that is twice as wide as and the same depth as the container the astilbe plant came in. Space the astilbe planting holes 12 inches apart in the garden bed. Remove the astilbe root ball from the container. Separate roots that circle the root ball and set the plant into the hole.

4. Pack soil around the astilbe root ball to hold the plant in place. Apply 1 inch of water to the soil around the plant to compact the soil and hydrate the root system.

5. Provide 1 to 2 inches of supplemental water to the astilbe plants each week when the rainfall amounts are less than 1 inch. Soak the soil to a depth of 6 to 8 inches with each water application to promote deep root growth.

6. Place a 2-inch layer of organic mulch around the astilbe plants to prevent weed growth that competes for soil nutrients and moisture. Refresh the mulch each year to maintain a 2-inch layer.

7. Remove spent blossoms by cutting them off the astilbe plant as they become dry. This will promote additional blossom growth through the growing season.

8. Apply a 5-10-5 fertilizer once a month during the growing season to promote flower production. Follow package instructions for an application rate based on the number of plants in the flowerbed.

9. Divide the astilbe plant every 3 to 4 years in the fall after flowering is complete to promote continues plant vigor.

References

• Cornell University: Growing Guide
• Missouri Botanical Garden: Astilbe chinesis
• Easy to Grow Bulbs: Astilbes