Light pruning at strategic times of the year can keep your agapanthus healthy and in bloom over the summer. Cutting back the spent foliage in early spring allows room for new growth to emerge and maintains a tidy appearance.
Evergreen varieties – Evergreen agapanthus varieties require no cutting back. However, you can trim both evergreen and deciduous plants as needed to remove dead, damaged or unsightly growth.
Agapanthus do well in pots. Cut back spent flowerheads after blooming and mulch annually with well-rotted compost or other organic matter.
"Unfortunately many people see agapanthus as a plant requiring no maintenance, however, it is important to get out into the garden and cut the seed heads off before they open and the seeds get blown around in the autumn wind."
Although leaves and flowers are damaged in high temperatures, they recover sending out new growth when conditions improve. Remove damaged leaves and flowers to improve the appearance of the clump. Agapanthus are most commonly seen in shades of blue and white.
Agapanthus pruning is also essential to encourage healthy growth. You can do this after the flowering season, cutting back the stems to around 10 cm above ground level for deciduous varieties, which include Agapanthus Melbourne, Agapanthus Galaxy White, and Agapanthus Little Galaxy.
Dividing and transplanting agapanthus
However, if left untouched for any length of time, they will become overcrowded and may flower poorly. Lifting and dividing agapanthus every 3 to 4 years will promote better flowering.
Avoid fertilizing your Agapanthus plants with high nitrogen fertilizers - use instead a balanced fertilizer such as 10-10-10 or 5-5-5, or slightly higher in phosphorus than nitrogen. Suspend any fertilizer to either potted or in-ground plants by late summer.
Repeat flowering Agapanthus for up to 6 months of the year.
Our Agapanthus varieties are designed to be tough enough to brave the Australian landscape, with good disease resistance, and drought and frost tolerance.
The Agapanthus plant leaves will turn yellow when put under direct light of very high intensity. Provide some shade for them during the afternoon hours at least. Overwatering will also turn the leaves of this plant yellow, soggy and plump.
They do not actually change colour but as the seeds germinate under the mother plant, seedling variation means these new plants could be white or blue! Once again, simply pruning the finished heads will stop the seed forming and ensure your aggies stay the colour you planted.
Common Pests That Can Cause Yellowing Agapanthus Plant Leaves. Insects such as aphids, mites, and thrips can damage the leaves, turning them yellow, while diseases like leaf spots or blight can also cause yellow leaves. Pest infestations can be controlled by using pesticides or other treatments.
To restrict its spread from your garden, deadhead stalks as flowers finish and don't dump unwanted plants. If you have a mass planting of agapanthus, deadheading sounds onerous, particularly for a plant that's often grown for its low maintenance.
Agapanthus grows and spreads by fleshy rhizomes that act as storage roots. The plant retains nutrients in its roots and may be divided to create more plants. Use a sharp shovel to dig up an established plant and divide it into several sections, each with roots and foliage.
Once you have decided which flowers need to be removed, simply take a sharp, sterilized pair of secateurs and cut off the flowering stalk close to the base of the plant. It does not really matter where on each stalk you choose to make your cut.
One of the most beautiful of the early summer blooming bulbs is the agapanthus or lily of the Nile. Although agapanthus do well here and are popular, they do not like it when temperatures reach the 90s. This causes dieback of the leaves – the tips of the leaves turn yellow, then brown.
It is important to pull out all roots from beneath the soil. Alternatively, cut the flower heads off before seeding to help prevent spreading. Brush cutting or mowing must be done regularly.
This plant can be easily propagated through division in late autumn to winter by carefully removing it from the ground or the pot. Gently shake off some of the soil so that you can see the roots and the individual plants. Carefully pull the individual plants apart making sure that each one retains its own roots.
Most Agapanthus bloom for around 6 weeks, however 'Flower of Love' has been specially bred to be much more floriferous than other varieties, for an incredible 10-12 weeks, starting around mid-July.
The best time to divide your Agapanthus is in the spring or early summer as soon as you notice the new shoots emerging or alternatively in the autumn. We would personally recommend the middle of September or October once your plants have finished flowering.