Tropaeolums tuberosum or mashuas are fantastic perennial climbers producing pretty nasturtium-like orange-red flowers and grey-green foliage. Native to the Andes, these vigorous herbaceous plants are particularly striking planted at the back of the garden border or against a fence.
Plant around 5 cm deep in moderately well-drained, fertile soil in full sun. Water freely during growth and apply a balanced fertiliser monthly: if you garden organically, liquid seaweed is ideal as it is organic and comes from a sustainable source. In frost-prone areas, provide a deep layer of mulch or lift and store tubers in a dry frost-free place with good air circulation over the winter months. Cut back spent foliage down to ground level in spring.
Always unpack on arrival and store in a cool place until ready to plant.
Potential problems, pests and diseases:
Aphids:these sap-eating insects can weaken plants and spread viruses. Whenever possible, pick off by hand using gloves.
Caterpillars:these larvae feed on a wide range of plant material including roots, stems, foliage and flowers, causing both aesthetic and structural damage. Whenever possible, put on gardening gloves and remove by hand. Alternatively, cover susceptible plants with a layer of horticultural fleece to prevent any risks of infestation.
Flea beetles: these small beetles feed on foliage, creating small holes and cavities in the upper side of the leaves. Although it is unlikely that established plants will sustain fatal damage, vulnerable seedlings may not survive. To prevent any risk of infestation, dispose of any deceased plant material and debris ahead of the winter months.
Snails and slugs:these pests enjoy munching on young shoots, stems, leaves and flowers. Watch out for damage!