Every gardener loves a challenge. Growing normal flowers, fruit and vegetables can be challenging enough with our unpredictable weather, but with so much talk about global warming it does tempt you to go beyond the normal and see what we can do with a few exotics. A wide range of exotic plants can now be found in most garden centres, so push the boat out and give some a try.
Way back in my apprenticeship days we only had a very limited range and most of them were under glass at Camperdown, such as bananas, bougainvilleas, canna, gardenias, clivias, passion fruit and some small fruited oranges. Outdoors we grew eucalyptus, caster oil plants and cordylines as summer dot plants for flower beds.
Today the range is extended to include Angel trumpets, the Tuberose, Spider lilies, and the white ginger lily. Some plants such as the Pineapple broom Cytisus battandieri, the New Zealand tea tree Leptospermum and the African Lily Agapanthus will grow fine outdoors all year round, but will die out if the winters get too cold.
There are very many more and most will either need a glasshouse for protection, a warm south facing wall, and others are quite hardy in the summer months but require to be brought indoors for the winter.
Several years ago mild winters were becoming normal for about ten years in a row, snow was a rarity unless you went up north and we all started to try a few less hardy plants. Eucalyptus, Cordyline australis palms, the date palm Phoenix dactylifera, Blue African lilies, the Pineapple broom and Leptospermum Red Damask all got planted in my garden and put on fantastic growth and a great show of flowers on some.
A passion fruit climber was planted beside my climbing rose Dublin Bay not really expecting it to grow. It just loved it and within two years it was in flower, growing wildly and threatening to take over my climbing rose.
Then in 2010, winter returned, temperatures plunged and stayed low for ages. In spring after the snows melted the damage was severe. Everything died out except the Eucalyptus, though it did lose a few leaves. Now we are in a mild wet cycle and know one knows how long this will last.
Exotics are now either kept in the greenhouse, at home in a light warm room or grown outdoors in the summer only.
Three plants worth trying are the tuberose known as Polianthes tuberose, the white ginger lily, Hedychium coronarium and the Peruvian daffodil or spider lily, Ismene festalis and sometimes called Hymenocallis festalis. All of these tender plants have highly scented white flowers.
They all need to be potted into a rich free draining compost and grown in a warm light room or heated glasshouse. Keep watered and feed fortnightly and in late summer you should be enjoying their powerful white scented flowers. The tuberose is difficult to flower in its second year unless you can get several weeks of good growth after flowering to build up the bulb for overwintering.
The lilies are easier and should be dried off for overwintering in their pots.
Angel Trumpets, known as Brugmansias and Indian Shot known as Canna can both be planted outdoors to flower in the summer months. Grow similarly as the indoor exotics but harden off and plant out in May in beds or tubs. Angel Trumpets flowers give off their fantastic scent in late evenings to attract night flying moths for pollination. They are perfect on a patio on a warm summers evening. Canna can be grown for its exotic foliage and flowers in a flower bed or tub. Both should be dug up in autumn, and kept fairly dry, but not too dry and keep in a frost free place.
I have had Canna overwinter perfectly fine in a dryish border, after I forgot to lift them in autumn, but the next year they grew and flowered quite happily. However that winter was mild.
Plant of the week
Crocus species are distinctly different from the large flowered hybrids in that they usually flower about two weeks earlier. The flowers may be smaller but they naturalise so easily that they readily create large bold drifts of colour. They are perfect amongst deciduous shrubs flowering in late February to early March before the shrubs have any leaves. There are numerous species, but my favourites all belong to just three main types. Crocus chrysanthus gives us the pastel coloured Cream Beauty and Blue Pearl, the pure white Snowbunting and the deep yellow Zwanenburg Bronze. The best Crocus sieberi are the lilac Firefly and the white Bowles White. Crocus tommasinianus is itself a very attractive lavender, and Ruby Giant is a very bold reddish purple.
They are always better planted in full sun otherwise the flowers may not open up fully.