Agapanthus, often called the “African Lily,” is immediately recognizable with its stunning, spherical clusters of blue or white flowers that bloom on tall stalks above lush, green strap-like leaves. They’re popular among gardeners for their exotic look and relatively low maintenance. However, one issue that crops up among agapanthus growers is sparse blooms or no blooms at all.
With all that lovely green foliage, it’s a letdown not to have the blossoms that go with it.
But if you want to fix your agapanthus woes, the time to do it is in the fall, a year beforehand.
Understanding the Agapanthus Blooming Cycle
To understand why you’ve been left high and dry without blooms, it’s helpful first to understand its blooming cycle. Agapanthus typically blooms during the summer months, with flowers appearing in mid to late summer, depending on the climate. These blooms last for several weeks and are followed by a period of dormancy where the plant focuses on storing energy for the next year.
It’s in that dormant period that next year’s flowers begin to form.
What that means is, if you want blooms next year, you need to take care of your agapanthus this year. The good news is that most blooming problems are easily fixed with adjustments to things like sunlight, water, feeding, and dividing.
Why Isn’t My Agapanthus Blooming?
If your agapanthus isn’t blooming or is producing fewer flowers than expected, there could be a variety of factors at play. Let’s take a look at the most common reasons why your agapanthus might not want to bloom:
Insufficient Sunlight
Indicator: Your plant has lots of lush green leaves but no flowers.
Agapanthus thrives in full sun, meaning they require at least 6 hours of direct sunlight per day to produce the big blooms. While some varieties will tolerate partial shade, it means just that – they will tolerate low light, but they won’t thrive. They generally struggle to bloom in low-light conditions.
If you want big blossoms, your plants need the full sun treatment. This may mean moving established plants somewhere they will receive more light.
It’s best to move plants when they’re dormant after the normal blooming cycle. This will allow the plant to set down roots and reestablish in its new location. Unfortunately, this may also mean another year with fewer to no blooms. In the end, it will be worth it to have properly thriving (and blooming) agapanthus.
Improper Watering
Indicator: If you notice flower buds forming but not opening.
While agapanthus is a drought-tolerant plant once established, it still needs adequate water during its growing season to produce flowers. On the other hand, too much water can lead to root rot, reducing the plant’s ability to bloom.
Water agapanthus deeply once or twice a week during especially dry periods and while new plants are settling in. Allow the soil to dry slightly between watering sessions. If your plant is in a pot, ensure that it has good drainage to avoid waterlogged soil. Mulching around the base of the plant can help retain moisture during hot weather, which promotes healthy bloom formation.
Overcrowding
Indicator: Small or a handful of blooms.
While agapanthus do well when they’re a little snug, they can become root-bound if in containers. Or in the ground, if the cluster they’re growing in becomes too compacted in the soil. When this happens, the plant focuses more energy on all of its foliage rather than producing flowers.
Divide and conquer to bloom.
It’s time to divide this popular perennial. The best time to do this is in the fall, once the plants have finished blooming. You can gently lift the clumps out of the earth and cut them with a clean and sterile knife. Let the cuts scab over for a day or two before planting them again in a new location.
If you have a potted agapanthus, you can pot it up into a larger container, moving up one pot size. Likewise, you can divide the plant so it will fit in its current container again and start a new plant in a different pot.
Cold or Frost Damage
Indicator: Stunted growth or no flowers.
Agapanthus is native to southern Africa and prefers mild, frost-free climates. If you live in an area with harsh winters, your agapanthus is probably suffering from cold damage, which can stunt or prevent flowering. Be sure you choose the right variety for your growing zone. Some agapanthus varieties are more cold-hardy than others.
If you live where agapanthus cannot survive the winters or will be cold-damaged, you can grow them in containers and bring them inside during the winter. Or you can dig them up each season and replant the bulbs in the spring, like a dahlia.
Cutting Back the Leaves
Indicator: Again, few or no blooms.
The leaves are necessary long after Agapanthus has finished blooming. They’re necessary for the plant to store energy and make new blooms. If you cut back the foliage immediately after they’ve finished blooming, you’ll end up with fewer flowers. Always let the foliage die back naturally, only trimming the leaves once they’ve turned brown.
Not Deadheading Spent Blooms
Indicator: Blooms are small and few.
It’s important to deadhead agapanthus, especially later in the blooming cycle. Deadheading your plant will redirect energy into forming new flowers rather than feeding dying blossoms.
There are plenty of good reasons to deadhead your agapanthus regularly.
Nutrient Deficiency
Indicator: Lots of foliage with no flowers.
This one is the big one. Agapanthus are heavy feeders, so if you aren’t getting a lot of blooms, this is probably the best place to start. A lack of nutrients, especially phosphorus (which is key for bloom production), can cause poor flowering. On the other hand, if you’re using a fertilizer with too much nitrogen, it will result in lush green foliage with very few flowers.
Starting in the spring, use a fertilizer that is higher in phosphorus and made especially for blooming plants.
There’s a reason agapanthus have a reputation for being low maintenance. It doesn’t take much attention now to ensure that come next year, your effort will be rewarded with a spectacular display of blooms.
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