Robinia hispida 'MACROPHYLLA' rose acacia, hairy locust

Macrophylla is a variety of hairy locust with fewer hairs along the stems and no thorns. The name applies to the size of leaves that are a little larger than on hairy locust and completely cover the plant. Locust emerges late in spring, flowers open up only a couple of weeks after the leaves, usually in late May. They are pea-like, rose-pink, formed in short clusters and last for 2-4 weeks.

In hot and sunny summer it blooms reliably for the second time at the end of July, in cold summers it may set fewer flowers throughout July and August. To bring the second blooming forward you can trim the new twigs to about half their size after the first flowering. Locust flowers on new branches so the plant will think it is time again to make a flower display.

Pinnate leaves are alternate, rich green green, composed of oval to rounded individual leaflets, larger than on black locust, larger than on hairy locust. This is low but vigorously growing shrub or small tree, often grafted at the base or on half-standard. Thanks to its small size it is ideal for small gardens, too.

It needs almost no maintenance and is very easy. Just find it a location protected from strong wind since branches are fragile and can easily break. Use ordinary, preferably less fertile soil with sand and do not fertilize. It is drought tolerant and dislikes wet conditions. Pruning can be done in early spring. Fully hardy to -29°C (USDA zone 5).

Last update 08-02-2012