General gardening topics

Why are my Daylilies not flowering? (Hemerocallis)

Last updated on May 4th, 2022

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Daylilies make a very popular choice in home landscapes and gardens because they produce a great deal of colour and give curb appeal. They are perennials that are known for their adaptation to a range of conditions and their ability to withstand the diverse UK climates. As the name suggests, each Daylily flower is open for only a single day. They provide a profuse range of flowers from a single plant, however, if you have been eagerly awaiting for the buds to open and they don’t end up flowering, it can be very upsetting.

Below we look at some of the reasons your Daylily might not be flowering and how you can hopefully resolve the issue.

What causes Daylilies not to flower?

When your Daylily stops producing flowers it can be quite alarming. If it isn’t producing flowers, you have to make sure first and foremost that you are doing what you need to do to provide it with the correct growing environment. There can be many reasons why your Hemerocallis might not be flowering at all, but the majority of them come down to incorrect growing conditions.


Provide them with the best growing conditions

Plant them in full sun

Most commonly, inadequate sunlight is the cause of poor flowering, and buds not developing. Planting your Hemerocallis in partial shade will cause it to struggle. If it doesn’t have access to enough light it will still live but it just won’t produce a consistent show of flowers because there’s only enough light to do one of two things and keeping the plant alive is its main goal. With this in mind, if you think it does not get enough sunlight, move the plant to a new position in autumn or spring.

Overcrowding

If the flowers have suddenly stopped but prior to now the plant was establishing itself quite well and producing flowers, the issue could be overcrowding.

A Daylily that once produced flowers but no longer does might simply not have enough space. As the plants grow and multiply, they have to compete for space and for nutrients in the soil. When this happens, especially when there is an inadequate amount, the size of the plant diminishes and the number of flowers they produce also diminishes. Consider lifting and dividing mature plants in autumn.

Learn more about growing Daylilies in this guide by clicking here

Hemerocallis gall midge causes flower buds to swell and not open

Hemerocallis gall midge is a common cause when flowers simply fail to open and usually happens in late May to early July. The larvae develop inside of your flower buds and then the flowers fail to open or get distorted.

Unfortunately, there is no known control but you should remove affected swollen buds. Using systemic neonicotinoid insecticide such as Bug Clear is thought to help but is not specifically stated to control the problem, although tests by the RHS have been positive.


Overview

If the issue is one of the improper growing conditions, you can try to rectify that by moving it to an area with more sunlight or breaking apart overcrowded plants and replanting them elsewhere in your garden.

If that isn’t the issue, and the correct growing conditions are in place, you can try to encourage more blooms on your Daylily by dividing it. Again, Hemerocallis can become overcrowded quite easily, and if you divide them and replant them somewhere else, (something you can do it anytime during the growing season but it is best done in autumn or spring) they will have more room and more nutrients that they can invest in producing more flowers for your enjoyment. 

If you are going to transplant after dividing your Hemerocallis, it is best to do it in the spring so that the plant has time to establish itself in the new area of your garden, otherwise you might have to wait for a whole year for the flowers to appear. When you plant it in a new location make sure that you plant the crown at the right level. If you plant it too deeply, this can cause decreased blooming which defeats the entire purpose of dividing and transplanting. 

Welcome to my site, my name is John and I have been lucky enough to work in horticultural nurseries for over 15 years in the UK. As the founder and editor as well as researcher, I have a City & Guilds Horticultural Qualifications which I proudly display on our About us page. I now work full time on this website where I review the very best gardening products and tools and write reliable gardening guides. Behind this site is an actual real person who has worked and has experience with the types of products we review as well as years of knowledge on the topics we cover from actual experience. You can reach out to me at john@pyracantha.co.uk

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