Planting & Growing Astilbe

Planting & Growing Astilbe

Image by Наталья Парамонова from Pixabay

Astilbes are saxifrage family members and clump-forming perennials that grow from strong rootstocks. The upright stems have fern-like green foliage and feathery pink, red, purple, or white plumes that extend above the foliage. Depending on the variety, the flower clusters can range in size from 6 inches to 2 feet, and the height of the plant can be anywhere between 6 inches and 5 feet.

They’ll give perennial borders, wet areas, containers, and groundcovers a burst of colour. The plant draws butterflies and repels deer and rabbits. The vibrant flowers are great for dried arrangements or floral cuttings.

Astilbe can be planted in the spring or the fall, but the hottest part of the summer should be avoided. If you must plant at that time, give the plant plenty of water until fresh growth appears. Although they are relatively slow-growing, once established, these plants will continue to bloom for many years before needing to be divided.

Astilbe Planting

Astilbes prefer light to moderate shade, although severe shadow will produce few and/or poor-quality flowers, and full sun will scorch the delicate foliage. These plants need the soil to be moist and humid, but it also needs to drain well and not pool, which would guarantee their failure. Astilbe are heavy feeders, therefore amend the soil with compost or aged manure (particularly in clay types). To increase drainage, mix perlite and coarse sand together.

When to Plant Astilbe

Astilbe are typically planted as little plants from garden supply stores in the spring or fall. For the home grower, starting from seed can be particularly challenging because astutebe can be challenging to germinate and the resulting plants typically have a short lifespan. It is advised to divide plants when growing fresh ones at home. As soon as you notice fresh growth in the astilbe plants in early spring, divide them.

How to Plant Astilbe

Based on the type, space purchased plants 1 to 3 feet apart. Up to 10 to 12 inches deep, dig the hole and loosen the soil. Add some compost and combine. Just below the soil line, plant the crown (where the plant’s roots and stems meet). Refill the hole with the earth you dug out. After planting, thoroughly water.

Dig holes that are 4 to 6 inches deep and twice as wide as the plant’s roots if you’re placing bare-root plants. The plants should be positioned with their crowns rooted 1 to 2 inches below the surface and their roots slightly fanning out and pointing downward. Put soil over the roots and firmly push. Water well and maintain moisture throughout (not soaked).

Astilbe Caring & Growing

Various types will bloom at various times between mid-spring and late summer. You may extend the bloom virtually the entire season by planting various astilbe species. The plumes continue to look wonderful as they fade and dry on the plant for several weeks while they are in flower. Since they won’t blossom once more, deadheading is not necessary.

Light

Astilbe plants grow in shade, but their flowers are more productive in areas where they can get some morning or dappled sun for an hour or two. The foliage will burn in direct sunlight in hot weather and on dry soils; therefore, some shade from the afternoon sun is necessary.

Soil

In loam, asters will give of their best. They enjoy using compost and fertiliser, and if necessary, they are content to have their feet in the water. They prefer soil that is retaining, including clay-based soils.
Astilbe is not drought-resistant, therefore let’s not deceive ourselves. They enjoy regular water, yet it is not necessary for there to be a lot of it to be regular. However, they will thrive in the water as they grow.

Water

Astilbe care includes regular, even watering throughout active growth, especially if planted in full sun.. Astilbe plants require more hydration in warmer climates, especially when grown in direct sunlight. They struggle to survive extended droughts; the plants will wither and die if the leaves are allowed to dry out for too long. Astilbe should only be deeply watered at the base once a week if it is not raining. Avoid overhead watering. Maintain a moist but not soaked soil.

Temperature and Humidity

Frost tolerance is high in Astilbe. As a result, they can withstand frost to well below -20C. Put down 2 inches of mulch around the stem after the first hard frost to shield the roots. Astilbe can flourish in situations that are only moderately humid, although during those times, it is susceptible to powdery mildew.

Fertilizer

Large feathery plumes result from the proper astilbe growing conditions and fertiliser. It is also recommended to amend the soil with compost on a regular basis and to fertilise with an organic product or phosphorus-rich fertiliser. Choose a fertiliser with a 5-10-5 or 10-10-10 composition. Rake the fertiliser into the soil two weeks before planting, or sprinkle a few granules on top of the soil after you’ve planted the astilbe. Fertilize the plant every spring when the soil is moist once it has established itself. Apply the fertiliser to the soil and avoid getting it on the leaves, especially if they are wet, as it will stick to them.

Types of Astilbe

Every year, new varieties are introduced, including newer breeds with darker foliage. Among the established standards are:

‘Fanal,’ with its dark green foliage and dark crimson flowers; grows to about 1-1/2 feet tall.

‘Irrlicht,’ up to 2 feet tall, for its dark green foliage and elegant white flowers.

‘Venus,’ with its bright green foliage and pink flowers; grows up to 3 feet tall.

‘Visions‘ has thicker raspberry flowers, stronger stems, and is more drought tolerant.

Pruning

The care of astutebe plants is minimal. The flower heads will continue to look lovely for many months as they dry on the plant. You can cut the flowers whenever they begin to look scraggly, or you can leave them up all winter and trim them back in the spring.

Propagating Astilbe

The simplest method of propagation is to divide mature plants. Every four years or so, division is advised to prevent the clumps from dying in the middle. Near the centre of the plant, arrange two hand forks back-to-back to divide. To gradually tease the plant apart, gently rock the handles back and forth. To further divide the plant into sections, repeat the process with each portion, making sure that each section has a sound bud.

Common Pests & Plant Diseases

Astilbes are virtually trouble-free, with few diseases or insects bothering them. Groundhogs and rabbits may nibble on the tender new growth, but once the plants have filled out, they usually do not suffer long-term damage.