The herbaceous perennial known as astilbe has at least 16 different varieties. Other common names for this plant are false goat’s beard and false spirea. The leaves of these plants are considered to be very beautiful. They are native to Eastern Asia and North America. Flowers with deep purple to magenta colors are especially loved by gardeners.
The plants have leaves that look like ferns, thick stems, and flowers in colors from white to purple. This astilbe has pure white flower spikes with dark green foliage. The plumes on this plant have tiny flowers that bloom from early summer to early fall. Ornamentals should be planted in the shade garden to protect them from hot weather. Avoid planting in full sun.
You can grow different varieties of flowers to receive a multitude of colorful blooms throughout the summer. A shorter version of the astilbe that only grows up to 2 feet tall is the Chinese astilbe. Astilbes are frequently given as a symbol of love because they are a symbol of patience and dedication.
How to Use Astilbes
We can’t remember how long ago Astilbes were introduced to the gardens at the farm, but they’ve been a feature there for quite some time. The White Garden features tall varieties of white Astilbes with graceful plumes that sway in the breeze in part-shade areas. The Shade Garden features Light pink, white, and red Astilbes growing amid Hostas, Hellebores, and Hydrangeas, providing a dappled light.
If space allows, plant Astilbes in multiples. Cluster plants in groups of threes or fives. Select plant varieties that have different heights and bloom at different times throughout the year. Choose a flowers in a range of colors to create a seamless look.
Astilbe plumes are a great way to add some vertical interest to your shady border plantings. They work well when they are surrounded by plants whose leaves pile up. Here are some of our favorite partners for these indispensable perennials:
- Alchemilla mollis (Lady’s Mantle)
- Perennial Geraniums
- Hakonechloas (Japanese Forest Grass)
- Aralia ‘Sun King’
Sun and Temperature
Astilbe generally prefers light or partial shade, but can tolerate full sun in northern zones if it gets shade in the afternoon. To get lovely flowers from this plant, you will need to give it at least 4-6 hours of sunlight each day. The dark green foliage of the plant will grow well even in deep shade.
This ornamental plant can grow in any of the USDA zones 3-8. The ideal temperature for growing plants is between 65 and 75 degrees Fahrenheit. They can’t survive in an environment that experiences extreme cold or heat. In winter, lay down a layer of mulch around the tree’s crown (after you’ve pruned it for the season) to protect the tree and its roots.
Water and Humidity
Water your astilbe in the morning to give it moisten it and help it prepare for the heat of the day. If the leaves on your plant start to curl and droop, this means the soil is too dry and you’ll need to give it a good watering. Although astilbes are not typically tolerant to drought, some varieties, including the Chinese astilbe, are more resistant to drought conditions than others.
To keep your plants healthy, water them deeply at least once a week, and apply mulch to help hold in the moisture. Dry soil can negatively impact your plants. To prevent water from splashing on the foliage and encourage fungal diseases, water the bottom of the plant. Water your plant until the ground freezes, then take steps to protect it from the winter weather.
Astilbe plants prefer well-drained soil, high in organic material. The organic matter in the soil helps retain moisture and prevents it from drying out during hot summer months. They do not grow well in heavy, clay soils and prefer a slightly acidic pH of 6.0. If your soil is more clay-based, adding extra organic matter like peat moss, perlite, or coarse sand can improve drainage.
Astilbe plants need a lot of nutrients to stay healthy and produce pretty flowers. The best time of year to fertilize your garden is in the spring. Look for a slow-release, balanced organic fertilizer with an NPK ratio of 3-1-2 (nitrogen, phosphorus, potassium). Make sure to amend your garden soil with compost regularly throughout the season. Late in the summer, switch to a high-nitrogen fertilizer to give your plants a boost.
After the flowers die in Autumn, you can still leave them where they are if you live in a warmer climate. This is because they will still look nice even when they’re dead. To help your astilbe plants survive a harsh winter, we recommend pruning them. Cut the foliage off close to the top of the soil. After the first freeze, put mulch around the plant to protect the roots. New foliage will grow in the spring.
There are three ways to propagate astilbe: start with astilbe seeds, divide existing plants, or take stem cuttings. Some options are preferred over others because of their advantages.
Sowing astilbe seeds is a slower process than other methods, but can be more fun. If you want to collect seeds from astilbe plants, it is best to get them from older plants. Seeds from older plants are more likely to grow than seeds from younger plants. You can also buy seeds from a local seed company and start them indoors 8 weeks before the last frost. Your transplants should be large enough to withstand outdoor temperatures, typically in late spring.
You can division astilbe plants to make more plants. You can divide plants in early spring or late fall when they aren’t actively growing. Water the plant thoroughly to make it easier to dig up the root ball. After the root ball is uncovered, break the clumps into smaller parts. Dig holes that are twice the size of the sections you want to plant. Improve the quality of the soil by adding compost. Water the divisions well to prevent shock.
The least popular method of propagation is stem cuttings. Cut off stems that are free from flower buds at any time during the growing season. Cut the stem of the plant above a leaf node, remove some of the lower leaves, and place the stem into prepared soil or water. water the cutting soil regularly but don’t let it get too wet, and wait at least 3 weeks for the plant to develop roots.
How To Plant a Potted Astilbe
Dig a hole that is about 1½ to 2 times as wide as the plant pot. The hole should be deep enough to accommodate the root ball. (Don’t make the hole too deep. When the plant is transferred to the hole, its crown – the point at which the roots meet the stem – should sit at the same level it does when the plant is in its pot.) Add a handful or two of compost and, using your trowel, mix the compost into the soil just as you would combine ingredients in a mixing bowl. If you loosen and enrich the soil in this way, you will make it easier for a new plant to grow.
Gently remove the Astilbe from its container. (Do not pull the plant by its leaves or stems. First, check the bottom of the pot for any roots that may have grown through the drainage holes. If they exist, gently tug them to see if they can be straightened. If not, cut them off. Next, invert the pot and knock gently on the bottom to see if the plant slides out. If it doesn’t, slide the blade of a knife around the inside edge of the pot (in much the same way you would separate a cake from a cake pan). If the plant is not yielding, use strong scissors to cut away the pot. Now that you have the plant in hand, use your thumbs to break up the root ball and untangle any roots that may be circling at the bottom. Set the plant in the prepared hole. Fill the area with soil and compost, and press it gently but firmly into place.
Watering: Water your new plant deeply and thoroughly. If you’re unsure of how much water to give your plant, fill a bowl with water that is approximately the same size as the pot the plant is living in. If the soil is already moist, you won’t have to water it as much. If the soil is dry, you may need to increase the amount of water you give it. Water your plant deeply once a week for the first few weeks.
Apply a 2″ layer of mulch around the planting area. The following will help to keep the ground cool and moist, promoting the perfect environment for your new plant to take root and grow.
How To Plant a Bareroot Astilbe
What is a bareroot? A dormant section of the plant’s roots is a section of the plant’s roots that has little to no top growth. It’s best to plant your bareroot tree as soon as possible after receiving your order. If you can’t plant the tree right away, you can store it in its packaging for up to a week in a cool, dark place, such as a basement or bottom of a closet. Do not add water to the packing material.
Unpack your bareroot plant by removing the plastic bag and packing material one hour before you plan to plant it. Discard the wrapping materials, including the plant ID tag. To prepare a bareroot plant for planting, fill a shallow bowl or pan with room-temperature water and soak the bareroot for at least 1 hour (or up to 8 hours). Be careful not to submerge any green growth, if evident. The soaking process rehydrates the bareroot which will give it a helpful head start on settling in.
While the root is soaking, dig a hole wide enough for the roots to spread out in and deep enough to plant the crown of the plant at the depth indicated on the plant label. Make sure the leaves on your Astilbe are above the level of the soil if they are beginning to show.
Remove the now-rehydrated bareroot from the water and gently spread out the roots. Put the unrooted plant in the hole with the stem pointing up, and arrange the roots in a natural-looking way. (If you’re unable to tell which end is up, position the bareroot sideways. The plant will generally know how to find the surface.) Holding the crown with one hand, backfill the hole with soil, filling in to prevent air pockets. Use your hands to gently pat down the soil around the base of the plant until it is packed tightly. Then, water the area to help the plant roots take hold and to get rid of any remaining air pockets in the soil.
You should not mulch directly over the site where you planted the bareroot plant, and avoid mulching over any sprouts that may be poking out of the soil surface. Form a doughnut shape with a 1-2 inch layer of mulch around the planting site. This will leave a hole for the bareroot to poke up its tender shoots without encountering too much resistance. The goal is to use the mulch to keep the area around the bareroot plant moist without suffocating your new plant.
Frequently Asked Questions
Can Astilbes grow in pots?
Astilbes grow well in containers as long as you keep them from drying out. Choose a pot that is large enough to accommodate the roots of your plant and fill it with potting soil that will help retain moisture.
Can Astilbes grow in full sun?
Astilbes will do best in light or moderate shade, unless you are in a northern growing zone where the soil does not dry out in the heat of summer.
What is the range of color for Astilbe blossoms?
There are many different colors of Astilbe plants, such as white, pink, red, and purple.
How tall do Astilbe plants get?
Astilbes come in a range of sizes, with the tallest varieties reaching up to 4 feet tall including the plume.
How long do Astilbes bloom?
Astilbes typically bloom for two to three weeks. But different varieties flower at various times. Choose your varieties of Astilbe carefully to design a colorful flower display that lasts most of the summer.
Do astilbe need to be cut back in the fall in order to encourage new growth in the spring?
Cut the stems of the plant back to 3-4 inches above the soil level in late autumn. You should cover the roots of your plants with mulch to protect them from the cold weather during the winter. Do not mulch your garden until the first freeze to prevent root rot and deter rodents from taking residence.
When should I prune astilbe?
Dead-heading astilbe will not result in new flowers growing. Deadhead the spent blooms regularly to encourage more flowers. Cut dead flowers off the plant regularly to promote more blooming. Prune the plant back in the fall to prepare it for winter.
How do you keep astilbe blooming all summer?
Provide plenty of nutrients to this heavy-feeding plant. For best results, fertilize in the spring or early summer with a slow-release fertilizer. Amend the soil regularly throughout the season with compost, and in late summer, switch to a high-nitrogen fertilizer. Do not place them in an area that receives full sun the entire day without any afternoon shade.