It's that time of year again when this amazing South African beauty burst into colour. Blues, whites, purples and violets adorne tall graceful stems. The bees love them almost as much as I do. We grow about 20 different verieties here at Blue Nurseries. From the dwalf A.'Tom Thumb' to the towering giant A. inapertus 'lydenburg'- which happens to be just opening as I write this.
If you want to grow Agapanthus successfully you must choose from the right group for your requirements. There are three basic groups: The first are the evergreen Preacox group, including Orientalis. The second is the deciduous group including Agapanthus campanulatus and A. inapertus . Finally there is the semi deciduous group, these are mainly cultivars which have hardier characteristics than some of the evergreen species.
Evergreen Agapanthus are generally not that hardy, unless you are lucky enough to live in southern coastal areas. For the rest of us these stunning plants can be grown in pots and moved to a greenhouse or very sheltered spot for winter. Deciduous Agapanthus are generally hardy and can be planted out in the garden or grown in pots. The deciduous group is the largest group by far and there is always new cultivars coming to the market every year. The semi evergreen plant group is variable when it comes to hardiness. It is best to check their RHS hardiness ratings before planting out. However, don’t be pot off as there are some really exciting new cultivars in this group, like Agapanthus ‘Fireworks’, which has been winning awards and rightly so.
Growing Agapanthus is not challenging, but there are a few key factors to success. Drainage is key, as Agapanthus cannot cope with wet roots in winter. The more sun the better, so avoid planting in full shade or somewhere they will be shaded by other plants. Water is only important in mid spring to flowering in June, having said that a regular water in hot weather is always a good idea. Some Agapanthus, particularly the A. Inapertus selections do like loads of water from early spring, but beware of late frosts and wet soil.
All agapanthus respond well to feeding. Use our specialist slow release fertiliser in March and again in September. We mix the slow release fertiliser with a thin top dressing of John Innes number 2 compost. Agapanthus in pots will require a regular liquid feed during the growing season - use a high potash feed in spring and a more balanced feed in September. Avoid high nitrogen feeds as this will encourage lots of leaf and fewer flowers.
Pruning back seed heads before seed is set will stop random seedlings growing. This is important if you want to maintain a particular cultivar as Agapanthus will usually revert to species. Tidying up the growth on Agapanthus in winter is something We don’t do. We find that folding the dry leaves back over the crowns helps protect the plant over winter. We wait for spring to tidy up all out Agapanthus in the garden. In very cold areas or when a ‘Beast from the East’ is likely, further protection can be applied to the dormant crowns. Use dry bark chip, fleece, straw or a combination of these to protect your Agapanthus, but remember to remove this as soon as the threat of severe weather has passed.
If you are looking for Agapanthus plants for sale go to Blue Nurseries for a great selection in 1 litre pots. Agapanthus slow release fertiliser is also available in handy 500gram resealable pots.