Hardening off tender plants

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.

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coldframe RHS/Tim Sandall

Quick facts

Suitable for: Seedlings and cuttings raised in protected conditions, half-hardy bedding plants and perennials
Timing: Late spring
Difficulty: Easy

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