• AGM plants

    AGM plants have been through a rigorous trial and assessment programme. They are:

    • Excellent for ordinary use in appropriate conditions
    • Available to buy
    • Of good constitution
    • Essentially stable in form & colour
    • Reasonably resistant to pests & diseases

Brugmansias can make impressively-sized patio plantsEven over just one summer, some of the tender plants that bring colour and drama to our patios and borders can develop into substantial plants.

Ornamental bananas and brugmansias (also known as daturas - see photo, left), for example, can mature into substantial specimens in just one season. In their second year, and beyond, their impact can be even more impressive – so why let the frost take its toll? Why not try to bring them through the winter?

Plants in containers are the easiest to manage as they can be manoeuvred into a sheltered corner by the house, into a greenhouse or into the conservatory. When they’re settled in their winter quarters be sure to put the pots on pot feet for the best drainage; soggy compost can be just as much a winter killer as cold. If they’re to spend the winter outside, you can use bubble wrap to protect the main stems.

Placing straw in the crown of Dicksonia antarctica (soft tree fern) for winter protection.Some plants in borders can be lifted and potted to move into a protected situation or they can be protected where they’re growing: ornamental bananas can be wrapped in bubblewrap, while tree ferns, especially their crowns, can be insulated with straw. Visit the Walled Gardens at the end of the canal near the main entrance at the RHS Garden Wisley to see good examples of protecting tender plants for the winter.

Digging up dahlia tubersThere are also plants which die back and are lifted and stored. Dahlias and cannas are the most familiar examples. Once the frost has blackened the foliage, cut the plants down almost to ground level (add the top growth to the compost heap), then lift the dahlia tubers or canna rhizomes carefully with a digging fork. Wash off all the soil, dry them carefully, and store them in boxes of almost dry multipurpose compost or sand. Keep them in a cool, but frost free place till spring. Begonia tubers can be stored in the same way; gladioli can be stored in paper bags.

Finally, be sure to label everything – you might think you’ll remember the varieties, but you won’t!

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