How to grow agapanthus

Charles Quest-Ritson's adventures with agapanthus.

Our new garden is on a chalk hillside above the River Itchen and I remembered that Lewis Palmer, raiser of the famous Agapanthus Headbourne hybrids, lived a couple of villages along the valley in the 1950s and 1960s. Agapanthus are amaryllids with narrow, strap-like leaves and most have alluring blue flowers on stems of anything from 6in to 6ft in height, in July and August. Tough, unfussy and drought-tolerant, they are perfect plants for chalky soils.

If Palmer raised agapanthus from seed, I reckoned, so could I. I looked at the cultivars we grew in France and decided that the best were Loch Hope and Agapanthus praecox Albiflorus. I made no effort to cross-pollinate them, but the bees must have had their way with the flowers because both plants set seed that I gathered in autumn.

Palmer wrote that it would germinate if sown in pots in March, which is what I did, using old clay pots filled with John Innes compost and extra grit for drainage. Then, having as yet no green-house, I put them in the warmest place I could think of, against a south wall of the house.

Nothing happened, so, last month, I concluded that that the seeds needed higher temperatures and more humidity. The answer was to cover the pots with clingfilm to replicate the ideal conditions for germination and, sure enough, the little black seeds turned into little green blades that filled the pots like newly sown grass.

Next March, I shall pot them up individually and grow them on. I used to grow agapanthus only in pots, but the flowers were smaller than I expected, so I planted them all out in the garden. I found that they were slow to flower generously, but a high-potash fertiliser (I use last year’s Tomorite) in late April greatly increased the production of flower-spikes.

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The first of my seedlings should flower in three years’ time, so I have grand visions already of beds filled with hundreds of young plants, each unique, from which I shall select the best for further work. Breeding new agapanthus brings quicker results than do the other things I’ve hybridised in the past; roses, apples and cherries take up to 10 years before you know whether or not you’ve produced a winner, but sowing open-pollinated seeds is a hit-and-miss approach to plant-breeding. That said, it’s how Alan Bloom, our greatest introducer of new herbaceous plants in the 20th century, raised many new plants simply sowing the seed and seeing what Nature could offer.

One of the good things about having no real garden as yet is that I can slip away to visit nurseries and look at other gardens, so now I’m off to see three National Collections of Agapanthus: at Fairweather’s Garden Centre not far away in Beaulieu, followed by the Hoyland Plant Centre in South Yorkshire and Pine Cottage Plants in north Devon (where Dick Fulcher raised the brilliant blue Northern Star). A friend also told me that Graham Gough at Marchants Hardy Plants in East Sussex ‘is breeding some crackers’, so, by the end of the month, I shall have visited all four points of the compass.

And, if the agapanthus-breeding bug really bites me, I shall be more professional about creating my crosses and transferring the pollen. There is quite a lot of colour variation from which to choose, both in the wild and in cultivation. I have great plans for dark-purple Mid-night Cascade and white Double Diamond, which is semi-double, but I prefer the true blue shades.

Some breeders, however, are now selecting agapanthus seedlings for longer flowering: the Australian raised Blue Storm flowers for nearly 10 weeks. Actually, Australia is one of those countries in which agapanthus have naturalised quite widely. I was once leading a party of Australians round the gardens of Insel Mainau in Germany and pointed out some striking clumps of agapanthus, only to be told ‘like, they’re weeds with us’. Now, I hope they will soon be like weeds with me, too.