“Humidity is Rising, Barometer’s Getting Low”, so sang the Weather Girls but you have to be like a Weather Girl to know the hardiness of the plants in your garden in order to have them survive the seasons.
Check the plant labels as you buy plants or set seeds for the following advice:
Hardy – means the plant can withstand UK temperatures to around -15C or lower. Most perennials like peonies, brunneras, lupins, hydrangeas and hostas will be hardy as they naturally die back in the Winter and grow afresh come the warmer Spring temperatures.
Frost Hardy – means the plant can survive a covering of frost down to about -5C but will need protection if lower temperatures are predicted. Plant frost hardy plants against a wall, fence or hedge to give them an added level of protection. You many have to fleece these plants in the Winter time.
Half-Hardy – means the plant can take just a touch a frost; lower temperatures will kill it off. Annual bedding plants like petunias, cosmos and salvias are usually treated as half-hardy plants as we are always advised not to plant them out in the garden until the risk of frost has passed. Pelargoniums are classed as half-hardy too and need to be taken indoors to a porch or window sill for the Winter.
Tender – means the plant cannot survive temperatures lower than 5C. These types of plants need to be moved indoors or to a heated greenhouse before the Winter temperatures really hit. Often the easiest way to grow tender plants like exotics which will not survive a UK Winter, is in pots so that they can easily moved to protect them.
Learning which plants in your garden need to be protected or moved before Winter will save you money in the long run so you do not keep losing these gorgeous plants every Winter. It will also save you time as not everything needs protected: many perennial plants are full hardy in a UK Winter and can simply be left to die back to do their thing to survive the colder temperatures and then rise again majestically from the soil come Springtime.