Geraniums: my hardy heroes - Telegraph Given that they were labelled as "geraniums," I assumed they were the hardy type, but when the tiny plug plants grew on a bit, it was obvious that they were pelargoniums. So with cold weather coming on, the pels are in a greenhouse, whereas my geraniums sleep rough outside. I have grown hardy geraniums in northern Japan where temperatures get down to -20C (-4F), so England is beautifully balmy by comparision. There are so many different geraniums that I never grow bored of them and keep discovering more adorable types. My mother gave me a boot load of G. Pratense 'Mrs Kendall Clark," which runs along the path to my office. It has beautiful, clear, pale blue flowers in June and July for a good six weeks, a relatively short period compared to some, such as the non-stop violet blue 'Rozanne" (June-November), but no matter, its ephemerality is all part of its beauty. Apparently 'Mrs Kendall Clarke" will also naturalise in meadows and orchards. With all geraniums (except the very narrow-leaved South African species), if you cut all the foliage and seed heads down to ground level after flowering they will generally repay you with more flowers and refreshed mounds of foliage. Most have neat mounds of foliage during winter too. Geraniums are not munched by rabbits, deer, slugs or snails, but are adored by bees. They tolerate a catholic range of soils, light conditions and moisture levels and are often worth trying in an awkward spot. Different types have slightly different preferences but if the awkward position does not prove a hit, you can bet your bottom dollar another spot will. For my own garden, I always prefer to buy bare root plants, which are less expensive and often establish better as their roots get going straight into soil proper rather than hanging on in the compost they arrive in. Plant straight away outside, unless it is even marginally frosty. If it is, keep them in a frost-free, light place, keeping their roots moist by placing compost around them until it is above freezing. Bare roots hate frost, but if you get a few sunny days, get them in the ground. If extreme weather is forecast soon after planting, add a couple of layers of fleece, bracken or sacking, just until they are weaned.