Warning as leaving plants in this part of the garden during the spring could 'ruin' them

Gardeners have been warned against leaving some plants in specific areas this spring or risk "ruining" them. While the UK saw high temperatures in April and May this year, some plants, especially ones with new growth, can still be vulnerable to the cold at this time of year.

As part of its gardening advice for spring, the (RHS) has cautioned that some plants could be susceptible to frosts until the end of May, especially overnight. The organisation added that the risk of frosts occurring can last until late May for "much of England and Wales", and June in Scotland and hilly areas of northern England and Wales.

Frosts occur when temperatures reach freezing levels (0C). This is particularly dangerous to new growth in the spring.

The RHS said: "Frost can affect many plants, and is particularly damaging to tender new growth and blossom in the spring. The risks of frost damage can be reduced by taking some simple steps to protect the plants in your garden."

Among the plants at risk of this are those that are left in areas of the garden that get lots of early morning sun. This may seem counterintuitive but the exposure to sudden warmth could cause plants to thaw too quickly.

"Plants exposed to early morning sun may thaw too rapidly after a frost, causing damage to flowers and young growth," the RHS said. "Camellia and magnolia flowers in particular can be ruined by a single frost"

To give young plants the best chance of survival if temperatures drop, the RHS recommends keeping them in a sheltered area of the garden.

Other ways to protect your plants

The RHS shared some other ways to keep your young plants safe if the weather gets colder.

These include:

• Choose plants that are reliably hardy and suited to your growing conditions
• Select planting positions carefully to avoid frost pockets
• Slightly tender plants should be grown in a warm sunny spot, e.g. against a south-facing wall
• Cover plants with a double layer of biodegradable or re-used old fleece, or other suitable protection such as an old sheet, overnight when frost is forecast
• Mulch the root area of evergreens, conifers, tender shrubs and tender perennials with a thick layer of organic matter to prevent the ground becoming frozen
• Move container-grown plants to a sheltered part of the garden in cold weather and provide some extra protection by wrapping the pot in bubble wrap
  
• Ensure tender plants are overwintered safely in the greenhouse by providing adequate heating or insulation
• Leave the previous seasons' growth on more tender plants until spring, for example penstemon, as this provides valuable frost protection during the winter
• Tender plants can be lifted or moved to a more sheltered position or greenhouse. If this isn't practical, then protect them by wrapping - examples include bananas and tree ferns. Lift tender perennials such as dahlias, cannas, pelargoniums and fuchsias before the first frosts
• Protect fruit and strawberries from frost by packing with bracken or straw
• Avoid applying nitrogen-rich fertilisers late in the season as they stimulate soft, sappy growth, which is especially vulnerable to frost damage
• Plant tender bedding plants out after the danger of frost has passed - this is generally early May in London and the south west, mid-May in the south of England, late May for much of England and Wales, and June in Scotland and hilly areas of northern England and Wales. Always harden off plants before planting outside

Hardening off refers to the process of acclimatising plants to colder temperatures.

The RHS said: "Plants raised indoors or in a greenhouse need to be acclimatised to cooler temperatures, lower humidity and increased air movement for about two to three weeks before they are planted outdoors. This 'toughening up' process is known as hardening off."

You can do this using a greenhouse or cold frame.

If you don't have these facilities, you can instead place plants in a sheltered position in front of a south-facing wall or hedge and cover with two layers of fleece to prevent sun scorch and temperature shock.