Madagascan Periwinkle (Catharanthus roseus)
Easy growing and thus very common perennials. It is moderately invasive, producing many seedlings around it. It is best grown in the sun, although it is fairly happy in the shade, but if the leaves turn yellow, it is probably needing more sun, or else is getting over-watered. The plant becomes quite straggly and especially when the hot season arrives, it is best to cut it back to a small size (making sure all the branches are fairly short), otherwise too many leaves can result in too much water loss and the plant may suddenly die. For the same reason, I move the plants in to the shade during summer.
The natural colour is a very boring pale purple, but a wide range of red/ purple/ pink/ white combinations are available.
The natural colour is a very boring pale purple, but a wide range of red/ purple/ pink/ white combinations are available.