A climbing perennial well suited to areas with mild winters, Tropaeolum, also known as Mashua, provides interest not only with its attractive Nasturtium-like foliage but with a profusion of exotic looking red and yellow tubular flowers in summer. This plant clings as it climbs, therefore requires a support to grow up, such as a fence with trellis/wires, obelisk or garden arch. In the right spot, this perennial bulb will grow back happily every year. It is important to note that it is half hardy, it can cope with occasional light frosts but won't tolerate freezing conditions very often. If your garden is in an area with mild winters, Tropaeolum is an interesting and unusal choice of climber to screen upright bare spaces with lush foliage and flowers. In colder areas, it is possible to grow them in pots which can be moved under cover for winter.

How to plant:

— Tropaeolum tubers are supplied in spring for planting between February and May. Unpack on arrival and plant as soon as possible while they are fresh for best results. Do not store tubers for prolonged periods as they will lose their freshness and viability.

— It is not recommended to plant Tropaeolum tubers directly into borders, even if there is no risk of frost. They will get off to a more reliable start if individually potted and grown on first, then transeferred to borders once in growth later in the season.

— Pot up into individual 15cm diameter pots with multipurpose compost ensuring the past year's dried stalk facing upwards.

— Water thoroughly after planting and position in a sheltered, sunny spot to grow on. Ensure the soil is kept moist while they are growing on in pots an throughout the growing season during the first year.

— Tropaeolum can also be grown permanently in patio containers. If you intend to grow your Mashua bulb in a patio container, there is no need to pot up and grow on first. You can plant directly into a 20cm+ diameter patio container filled with good quality multipurpose compost the same was as described for potting up above.

— If your Tropaeolum is intended for a border, you can transfer it from the temporary pot it was started in into the border once risk of frost has past (after around early May), and once the tubers have established some growth. The plant will be ready to transfer into a border once it easily comes out of the pot with the soil held together by the roots. This typically takes a few months from planting, depending on the size of the pot and when it was planted. Allow the compost in the pot to dry slightly before removing the pot, this will help the soil stay attached to the roots during transfer.

— Choose a position in full sun with moist but well-drained soil. Space the plants 20-30cm apart from each other. Add multipurpose compost to each planting hole when planting, this will add nutrients as well as providing a soft medium to help the new roots grow. Water thoroughly after planting.

— Push a cane into the soil next to the plant for it to initially attach itself to and to help guide it to the main growing support. Monitor the plant closely during the first growing season, ensuring the soil is kept moist and that more established plants or weeds are not encroaching or smothering.

— Tropaeolum are not fully hardy and can't tolerate regular freezing temperatures. When potting up during spring while there is still a risk of frost, start in a cool, bright place indoors or in an unheated greenhouse.

Aftercare

— Tropaeolum typically remains quite compact and may not flower in the first year, however it should produce attractive leaves by around June depending on when it was planted. It is common for Tropaeolum to take 2-3 months to sprout. It may take between 1-3 years for the plant to to reach full size make an impact.

— Foliage should be left intact after flowering, as this helps feed the tubers for the following year. As the plant dies back naturally in autumn, old stems can be cut down to ground level.

— Re-pot container grown plants annually, or top dress with a generous mulch of compost to feed the plant.

— In areas where frost or freezing temperatures are likely over winter, lift Tropaeolum tubers out of the ground, allow to dry and then store in cool, dry and frost free conditions for winter. If grown in containers, they can be moved under cover for winter. In areas with mild winters, Tropaeolum will benefit from a topping of mulch over winter.