Mashua

Tropaeolum tuberosum.

Another fabulous tuber from the Andes. An exquisitely beautiful, climbing Nasturtium with deep orange-red trumpet flowers and smooth skinned, bulbous, elongated tubers . The tubers have a lovely pepper flavour when fresh, mellowing, with a vanilla edge when cooked. As with nasturtiums, the young leaves are fabulous in salad!

Tubers are frost tender so pot them up, pointed end down, in moist but free draining compost on receipt, and keep in a polytunnel or greenhouse until the frosts have passed. Then plant out in a warm, sunny spot (ideally with roots in shade for the largest possible crop) in well drained soil.

Ideally harvest after a light frost as the flavour is improved but beware harder frosts as they will damage the tubers. Store tubers in a dry, cool, frost-free place, potting up the smaller tubers and planting out after the frosts. In milder areas tubers (which are formed very near the soil surface) can be thickly mulched to take them through the winter.

Plant out after the frosts about 30 cm apart, they will need some support as they can easily climb over a metre if doing well with lots of warm sunshine. Water your mashua well or they will stop growing so a good thick mulch will help. Leave the plants as long as possible into the autumn and lift once the foliage has completely died back, once dried the tubers can be stored in the same way you would your potatoes.