Anyone who has observed centranthus or lamptranthus growing away and naturalised in coastal hedgerows or banks may also have admired Gladiolus byzantinus which has also managed to naturalise itself in grassy banks around and within our gardens. As I write this I am looking at a new group of three plants flowering away in an unmown grass bank in an area where this plant has not been grown in cultivation for decades. At Burncoose its seeds have somehow jumped over the high walls of our walled garden and now appear along the drive where we have to remember not to cut them until after they have seeded and the leaves have gone brown.
Gladiolus byzantinus is a vigorous perennial with linear leaves of up to about 2ft or more. It produces flowering spikes in May or June with us that each have up to 20 funnel shaped deep magenta flowers which are up to 2in across. The plant multiplies and spreads freely from its corms as well as by seed. In the nursery it flowers away in pots from corms sown in late February which may need small cane stakes to keep its flowers upright in the wind. An easy and satisfying plant to grow which is native to Spain, North Africa and Sicily. The corms can readily be separated and moved once the plant is dormant.
G. byzantinus is perfectly hardy with us but it may be more borderline away from southern and western coasts. Nevertheless it is cheap to acquire as a seed or as corms and well worth growing for its spectacular flowers even if you do occasionally lose it to cold. A mulching of the border where it grows would probably ensure success.
If you grow no other gladioli in your garden this species is certainly worth trying. It is far less trouble than the much taller growing and more slug troubled cultivated varieties of gladioli.
