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Why are my Daylilies not flowering (Hemerocallis)
Last Updated on April 3, 2020 by John
Daylilies make for a very popular choice in home landscapes and gardens because they have a great deal of colour and 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 day lily is open for only a single day. They provide a profuse range of flowers from a single plant, however, when they aren’t flowering, it can be very upsetting.
Below we look at some of the reasons your Daylily might not be flowering and how to 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 give it the correct growing environment. There can be many reasons why your day lily may not be flowering at all but the majority of them come down to incorrect growing conditions.
Provide the best growing conditions
Plant in full sun
Most commonly inadequate sunlight is the course for poor flowering and buds, not developing. Planting your day lily in partial shade will cause it to struggle. If it doesn’t have 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 it’s main imperative. With this in mind, if you think it does not get enough sunlight, move the plant to a new position in autumn or spring.
If the flowers has 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 diminishes. Consider lifting and dividing mature plants in autumn.
Hemerocallis gall midge which causes flowers to swell and not open
Hemerocallis gall midge is a common cause when flowers simply fail to open and usually happens late May to early July. The larvae develop inside of your flower buds and then the flowers fail to open or they get distorted.
Unfortunately, there is no known control but you should remove affected swollen buds. Using systemic neonicotinoid insecticide such as Bug Clear is though to help but is not specifically stated to control the problem but test by the RHS has been positive.
If the issue is one of improper growing conditions, you can try to rectify that by moving it to an area with more sunlight, or breaking apart over crowded areas and dispersing them elsewhere in your garden.
If that isn’t the issue, and proper growing conditions are in place, you can try to encourage more blooms on your daylily by dividing it. Again, daylilies can get overcrowded very easily and if you divide them and replant them somewhere else, something you can do it anytime during the growing season but its 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 day lily, 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 blooms to appear for a whole year. 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.