One of the few plants which will survive in dry soil comprised largely only of sea sand is the tamarisk. This totally hardy shrub or small tree is a common coastline plant where it can be used to help protect coastal sand dunes or create a windbreak around the most exposed seaside garden. No amount of salt spray or salt laden gales will hurt this plant which, at Caerhays, is often adorned with seaweed blown up from the sea in southerly gales. In Seaview on the Isle of Wight it is virtually the only shrub which can be grown in seashore gardens that can also experience survive extreme drought.
Tamarisk species come from Asia and Mediterranean countries. In southern Italy they are common street trees along the coastline and grow into rather larger trees than in the UK. The other interesting attribute of these plants is that they have different flowering seasons. Tamarix tetandra flowers in May and June while Tamarix ramosissima varieties flower from midsummer into the autumn.
T. tetandra has arching purple-brown new shoots and needle like leaves. It produces light pink flowers in lateral racemes which are 2in long on old shoots. T. ramosissima also has feathery red-brown new shoots and similar leaves but the racemes are longer and appear later in the year on the new growth.
Forms of T. ramosissima can be white (‘Hulsdonk Wonder’), rose-pink (‘Rosea’) or pink (‘Pink Cascade’). Intermingling the colours produces a good show.
Once mature, tamarix do need some pruning to remove broken branches and to improve the overall shape of the plant which can become top heavy. T. ramosissima can be pruned harder and more regularly than T. tetandra because it flowers on the new growth rather than old shoots. Pruning therefore improves the flowering performance.
We grow this plant from hardwood cuttings set in winter in a cold frame with a mix of sand and soil. Semi ripe cuttings in late summer are quite viable but you will get a larger plant more quickly from hardwood cuttings.