Knowing how to propagate astilbe is quite simple, and you can either start them from seeds or divisions. There are different cultivars to choose from, and with the proper propagation technique, you can easily create more of your favourite plants and have more of this perennial that will give you a show from late spring to early summer. If you want flowers in autumn, you can even select astilbes that will bloom around this period.
Astilbes will thrive from zones 3 to 8, but you can also grow them in the polytunnel to avoid development drawbacks. Remember that even though one can say that a plant is easy to cultivate, rooting is still a sensitive process. A stable environment should encourage astilbes to develop faster and grow vigorous until you can transplant them outdoors.
Comprehensive Guide On How To Propagate Astilbe
Method #1. Seeds
The first method for propagating astilbe is by using seeds. However, note that choosing this technique is not a guaranteed way to create a clone of your favourite astilbe variety. The resulting plant’s characteristics from seeds will vary, and the chances of it being the same as the parent plant are low.
If you prefer to start astilbes from seeds, you can purchase them or collect them from your existing plants. A helpful tip to remember is to grow aged seeds instead of fresh ones since they germinate faster. More so, the best way to germinate astilbe seeds is by starting them indoors.
Sowing
Use a tray and fill it with a seed-starting mix. You can plant the seeds at ¼ inch below the medium, but allocate that each cell to only has one seed. Mist the mix to keep it moist, but be mindful not to oversaturate it.
To further help with germination, cover the tray with plastic and place it somewhere bright and warm. You can also check the polytunnel temperature so that it’s around 70°F in the day and 50°F at night. As for maintenance, you can check the medium weekly if it needs some misting.
Transplanting
Once the seeds germinated and developed into seedlings around 4 inches tall, you can remove the cover. Transplant the astilbe seedlings in the UK garden after the danger of frost has passed. Choose an area in your British garden that receives shade and has well-draining, fertile, and loose soil.
Method #2. Division
The more preferred method of the UK gardeners for propagating astilbe is by division. You can purchase bare roots and plant them yourself. More so, dividing mature astilbe plants should be part of your general maintenance every three years to keep them healthy.
Digging
The ideal time to divide astilbe is early in spring or late in autumn before growing and when the plants have also died back. You can make lifting much easier by digging around the perimeter of the mature astilbe plant. Digging also makes it unlikely for you to damage the rhizomes of the plant accidentally.
Sectioning and transplanting
Some gardeners in the UK also find it easy to divide the astilbe by lifting the whole plant with the root ball still intact. You can then use a shovel to divide the roots to create around four sections. However, make sure that you have also removed all the damaged roots before planting and do so as quickly as possible to prevent them from drying.
For the new location, you can allocate a depth of 6 inches for the rhizomes. It’s also best to amend the area with compost and ensure that they are in partial shade to prevent sunlight damage. More so, moist soil is crucial to support the establishment of the divisions.
Maintaining Astilbe
To further help with your astilbe plants’ growth and health, you want to learn about their ideal conditions and requirements. For example, astilbe’s perfect location should be bright and provide shade to burn with direct sunlight. You also want a well-draining medium that retains moisture well.
Remember that astilbe requires water more than other plants, so watering deeply is a common practice. However, never leave them in standing water as this can encourage rot. Feeding, on the other hand, is beneficial every spring with a balanced fertiliser.
Can you extend the foliage and blooming period of astilbe? You can elongate the flowering of astilbe by removing the dead and faded flowers. Some gardeners in the UK even cut the spent stems to maintain the plant’s foliage after blooming.
Conclusion
If you want a plant that will put on a show in spring, summer, and autumn, astilbes make an excellent consideration. Knowing how to propagate astilbe is relatively simple, and you can create more plants for your British garden without issues. If you have a greenhouse, you may even find it more comfortable to root your plants indoors for quicker transplanting outdoors.
You can choose to start astilbes from seeds or divisions. Germination can take longer, so you want to use aged seeds instead of fresh ones. However, you can sow the seeds indoors and maintain the ideal conditions to help you with their sprouting.
On the other hand, Dividing astilbe has the advantage of creating exact copies of your parent plant, and it also works as a maintenance practice to prevent overcrowding and keep the plants healthy. In general, choose an area with fertile, moist, and well-draining soil for transplanting, and provide partial shade for astilbe to guarantee healthy growth.