How to care for perennials in winter
Year after year, perennial plants provide UK gardeners with the colour and vibrance they need to brighten up any landscape. Their ability to weather harsh British winters, while at the same time maintaining their attractive foliage, ensure they remain a firm favourite in gardens across the country.
From radiant hibiscus to lush green heucheras, a well planned perennial garden can provide an ever-evolving variety of flowers for years to come. However, in order for your perennials to prosper, they need to be correctly prepared for winter. Here are the key tips you need to help plant, prune and care for perennials during the winter months.
Can you plant perennials in winter?
While it is certainly true that perennials will only become the star performers of your flower beds during the summer months, this is not to say planting them in winter is a bad idea. On the contrary, there is absolutely no reason why you should avoid planting your perennials in winter and, in fact, there are actually advantages in doing so.
Unlike annuals - plants that complete their entire life cycle within one growing season - perennials will continue to flourish for at least two years. Subsequently, the winter months become a crucial period in their life cycle as this is the time perennials will typically bed down below rotting leaves and get used to their new surroundings. Indeed, unlike those planted during their summer prime, perennials planted in wintertime won’t need to be watered until the drier conditions are welcomed in with the start of spring. Given the necessary time and attention, as well as the correct methods and approach, perennials planted during the winter months will actually thrive in this cooler climate, perfectly preparing themselves for their summer splendour.
Image alt text: aster perennial plant in bloom
How to prune perennials for winter
In order to ensure your perennials continue to prosper and return to their prime during the spring and summer months, winter pruning is essential. Whether you are planting your cirsium or lupin in the dead of winter, or maintaining your prize perennials through their first winter period, there are three key pruning techniques you need to take advantage of:
Cut back stems, reduce watering and dig up bulbs
As summer turns to autumn, and your perennials have finished for the season, stems should be cut back to between 6 and 8 inches from the ground and watering should be drastically reduced. This will help harden off the plant in preparation for cooler and damp conditions. Sensitive perennial bulbs, such as dahlias, canna and gladiolus, should also be dug up or ‘lifted’ before the first ground frost of the year. These bulbs should be stored indoors and can be replanted in spring.
Winter is also the perfect time to feed your perennials. Applying a 4 to 6 inch layer of compost is a highly effective method. The compost will release nutrients to the plants, improve the soil structure of your beds, and help replenish your perennials over the winter period.
Finally, when cold weather begins to strike regularly, mulching is essential. Old mulch around the beds of your perennials should be removed and replaced with leaves, straw, grass clippings, bark, sawdust or pine needles. This additional layer provides protection for the more sensitive plants and will insulate your bed.
These simple techniques will not only help to ensure your perennials survive winter, but they will encourage your plants to actively thrive during this period.