A little watering is likely to be vital even during winter, as certain types of plants are still likely to need the occasional drink. This need is increasing as the effects of climate change intensify, resulting in greater extremes of weather – it’s now not uncommon to experience extensive periods without rain. Plus, the growing season is a full month longer than previously considered ‘typical’, so winter-dormant plants are starting to come into growth earlier. While the cause of browning leaves and shoot dieback is often attributed to frost damage, very often the culprit is a lack of water. It’s therefore important to keep an eye on vulnerable plants, particularly those in pots, in case they need watering in winter.
Water vulnerable plants
Evergreens, including conifers and wintergreen perennials, continue to grow during winter, albeit much more slowly than in other seasons. Anything newly planted is particularly at risk.
Climbers and wall shrubs that are evergreen and growing against the walls of buildings are often in a ‘rain shadow’ created both by the walls and by overhanging roof eaves. Plus, they produce a lot of growth from a small footprint.
In late winter if conditions are dry, water spring bulbs and perennials that are emerging into growth. Dryness is a common cause of bulb ‘blindness’ or failure to flower.
Check container grown plants
Container-grown plants are prone to drying out as the whole root zone is above ground and constricted by the size of the pot. Those at highest risk are evergreens where the foliage effectively forms an ‘umbrella’ that prevents rain from getting through. Be aware that terracotta pots are porous and likely to dry out fastest.
Conversely, make sure containers don’t become waterlogged, as roots need air as well as water, plus soggy compost can freeze solid and kill the plant. Avoid using saucers under pots, and either raise just off the ground on pot feet or stand on gravel to ensure free drainage.
Test the soil
If unsure whether any plants need water or not, whether in a container or the ground, use a narrow trowel to make a hole 10-15cm deep by the roots, and test the soil moisture with your finger. How much should I water in winter is a common question that is hard to answer, because it depends on the amount of rain and type of soil. The aim is to have soil that is moist, but not soggy.
Water wisely
Water infrequently but thoroughly. Ideally, water in the morning, pouring water directly onto the soil rather than the leaves, which can cause rot or encourage fungal diseases. Hoses make watering easy but are liable to damage during freezing weather. Drain hose pipes, and store under cover when not in use,
Keep an eye on the weather
Try not to water during freezing conditions or when frost is forecast. However, don’t worry too much about water freezing your plants unless they are in pots, which are most susceptible. Mitigate the effects of cold by standing pots close together and against walls, and water only as much as needed to moisten the compost. While observing rainfall is an obvious guide to whether watering is needed, wind direction is less obvious, but important to be aware of. Winds from the east have travelled over mainland Europe and are extremely drying as well as cold. The stronger the wind, the faster your plants dry out.
