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Growing hemerocallis – How to plant and grow Daylilies
Last Updated on April 27, 2020 by John
Daylilies are beautiful plants that get their name from the fact that they only produce flowers that last one day. However, they produce an abundance of flowers over the course of the summer months so you get a display of flowers on a daily basis somewhat regularly so the name can be a little miss-leading.
You can choose a range of varieties that come in a large selection of colours including burgundy red, orange, even yellow flowers and everything in between. The stems rise up out of the foliage and bring with them an array of delight no matter where you live and they grow well in most soil including poorer clay soils but they dislike dry soils and positions prone to waterlogging.
They reach a height up to an impressive 1.5 meters and a spread up around 1 meter but you can get smaller varieties which are better suited for containers.
Most daylilies prefer sun and are best planted in April or the end of September with flowering times that range between the end of May to around August.
Planting daylilies (Hemerocallis)
Plant in fertile well-drained soil
Daylilies do best with fertile soil that is well-draining. However, they are cherished across the UK because of their ability to tolerate poor soil including heavy clay soil as long as it does not become waterlogged it’s well-worth digging in plenty of organic matter and grit to improve drainage.
Don’t plant in heavy shade or areas prone to drying out over Summer
Realistically you only want to avoid planting them in heavy shade or an area that’s going to dry out over the summer.
Growing them in containers
You can grow them in containers if you have a problem with your soil structure or with moisture retention or simply want to grow them in pots on a patio, this can help get the abundance of flowers that you want.
In some situations, if they are overcrowded you might end up dividing an existing plant from your garden and putting it in a container or dividing a congested plant in a pot. We recommend using compost with good water retention so something like John Innes potting compost is perfect.
Planting bare root plants purchased from garden centres and nurseries
You can purchase bare-root daylilies at a garden center but you’ll have to check over the packets to make sure that the packet is firm and you can see small shoots coming out. If you see any bare-root daylilies with long, pale shoots, you don’t want these.
If you decide to buy bare-root plants rather than the potted alternative, you want to put them in a pot first instead of directly in the ground like you would pot grown plants using a soil-based compost as explained above.
You should keep those pots in a cold frame or a cold greenhouse if you have one until they are strong enough to be planted outside, something you should schedule in the spring or the Autumn once they have established themselves in the pots.
Daylilies are pretty easy once they are given the right conditions in which to grow. Of course, there might be problems where your daylilies aren’t producing the flowers that you want and in these cases, you can add a multi-purpose fertilizer at an average of 60g per square meter or what is stated on the packet.
Mulch around the base of plants to help retain moisture
You can also lay some mulch around your established plants at the beginning of Spring to help conserve moisture, this will also help suppress weeds. Things like manure or garden compost work very well for this as well as bark which works better for preventing weeds.
Prune to help reduce the risk of hemerocallis gall midge
Daylilies don’t need a lot of pruning or any type of training or support. However, we do recommend deadheading after flowering to improve the overall look of the plant and to help reduce the risk of hemerocallis gall midge infestations, beyond that you don’t have to do anything.
Hemerocallis gall midge, slugs and aphids
There are no significant diseases that daylilies have to contend with but one of the biggest pests that you will need to tackle is the Hemerocallis gall midge. The larvae develop inside of your flower buds and then the flowers fail to open or they get distorted. Other common pests you might have a problem with include slugs, snails, or aphids which can be controlled with slug traps and pesticides for aphids or good old soap and water.
Propagating by division
If you have a successful Daylily you can divide the larger clumps in the spring or autumn and then replant them elsewhere in your garden or pot them up into containers. This is a great thing to do every few years anyway because an overcrowded Daylily which naturally expands every season will not have enough nutrients in a given space to produce as many flowers. You can ensure you get the same flush of flowers if you divide and transplant from a bigger plant on a regular basis. Simply life mature plants and divide into section approximately 6-8 inches wide and plant giving them plenty of room to grow, ideally at least 1ft between section if planting in clumps.