Troubleshooting Astilbe Diseases Overcoming Problems Growing Astilbe Plants

What's wrong with my astilbe?

Diseases of Astilbe Plants

Powdery mildew and cercospora leaf spot are two astilbe plant diseases that are fungal in origin. Both can present serious problems growing astilbe in the garden. When you first spot powdery mildew infection, it looks like someone sprinkled white power over the plant's leaves.

Why is my astilbe dying?

Astilbes begin to wilt, sometimes quickly, when they're exposed to too much sun. The hot summer sun can also heat up and dry out the soil. Another symptom of too much sun is leaf scorching; the edges of the leaves may appear burnt or begin to shrivel.

Why is my astilbe not growing?

Soil and Moisture – Although astilbe prefers organic, well-drained, acidic soil, it's important that the plant is relatively moisture retentive. ... Fertilizer – Astilbe plants are heavy feeders and may not bloom without adequate nutrition; this is a common reason for an astilbe not flowering.

What causes astilbe leaves to brown?

High temperatures, dry soil, windy conditions. Move the plants to a shady, moist location. Note that leafhopper feeding can also cause leaf tips to redden and brown.

How often should I water Astilbe?

It's best to water deeply when you water (not everyday sprinkling). Astilbes spread quickly and form broad clumps. Their crowns often rise above the soil as they grow, so make sure to cover them with humus-rich soil or lift and replant the clumps.

Should I deadhead Astilbe?

Deadheading astilbe won't encourage new flowers, so you should leave them in place through the fall. Eventually, the flowers will dry on the stalks but should stay in place. When winterizing astilbe plants, you can cut all the foliage off, leaving just a 3-inch (7.5 cm) stem above ground.

Does astilbe need sun or shade?

Light: Astible grows best in part shade. It can thrive in full sun, but will need shade in the afternoon in hot summer climates. In full shade, flowering will be reduced. Soil: Astilbe thrives in moist, well-drained soil that has a slightly acidic pH (6.0).

How many hours of sun is part shade?

Part shade is also defined as four to six hours of direct sun per day, but most of that should come in the morning hours when the sun's rays are less intense.

Do Astilbes bloom all summer?

Astilbes bloom between late spring and late summer. They flower over a fairly long season since each flower plume consists of hundreds of densely packed tiny flowers, opening in succession.

How do I get my astilbe to bloom again?

The trick to extending astilbe plant bloom time is to install a variety of cultivars from each blooming period. Consider the varieties “Europa” (pale pink), “Avalanche” (white), or Fanal (deep red) if you want astilbe with late spring or early summer bloom time.

What can I plant next to astilbe?

There are quite a few plants that meet these astilbe companion planting qualifications. Rhododendrons, azaleas, and hostas all prefer shade and grow in a very wide range of hardiness zones. Coral bells are a relative of astilbe and have more or less identical planting requirements.

How do I get my astilbe to bloom?

Also astilbe set flower buds for next year in the late summer early fall so fertilizer applications at that time are the most beneficial for flower bud formation. Keep them well watered also. Hope this helps (Thanks, Greg!).

What to do with astilbe after flowering?

Caring for astilbes

Astilbes are easy to care for, provided they're growing in the right growing conditions. They don't need deadheading. Simply cut back plants after flowering and divide every three or four years.

How do you care for Astilbe?

All astilbes, even the more drought-tolerant varieties, prefer cool, moist soil rich in organic matter. Keep the soil evenly damp but not soggy, especially during the winter when plants are dormant. Avoid planting in heavy clay soils and sites with poor drainage.

How do you dry Astilbe?

Astilbe, hydrangea, sage, yarrow and ornamental grasses are very easy to dry. Collect the flowers in lose bundles by tying the stem ends together with a piece of string or a rubber band. You can hang them upside down or place them on a rack or screen raised above ground level in a dark, dry and warm location.

Does astilbe need fertilizer?

Astilbe plants need phosphorus to bloom, so choose a fertilizer with the makeup of 5-10-5 or 10-10-10. Rake the fertilizer into the soil two weeks before you plant, or sprinkle a few granules onto the soil after the astilbe has been planted.

How long do astilbe flowers last?

They bloom for 2 to 3 weeks. Depending on the variety, astilbes flower from early to late summer. Early blooming varieties begin to flower in late May or June while late bloomers begin in late July or early August.

Are astilbe poisonous to dogs?

Astilbe may be some of the taller plants in your perennial shade garden, as they grow to heights between 2 and 5 feet. ... This is one of the easier-to-grow shade perennials since it requires minimal care beyond basic watering. Both astilbe and yellow corydalis are non-toxic to dogs.

When can I divide astilbe?

You can also divide the plant (digging a piece out with a shovel) in early spring or fall, but not before the third year. Dividing your astilbes is healthy for the plant and encourages growth, and divided plants will look exactly like the original plant.

Do Astilbes spread?

Most astilbes spread easily, so divide your plants every 3 to 5 years to prevent overcrowding and to keep them vigorous and healthy.

Will Astilbe grow under trees?

Even grass and supposed "shade plants" such as azaleas, astilbes and ferns have a hard time growing under trees. That's because this is dry shade - with big-root competition to boot.