|Frosts are threatening and it's time to bring frost tender plants under glass for winter protection. As light levels and temperatures drop, it is noticeable that the greenhouse feels slightly damp. Air circulation is important to overwinter plants successfully, damp and mould are as big an enemy as the cold and frost; a good tip is to raise the plants up from the ground and not to pack them in too closely together. This way air circulates around the plant and will help it survive the winter without succumbing to Botrytis, grey mould. This is really easy to do, just put a few bricks on the greenhouse floor and lay couple of old planks along the bricks to make a low trestle. In this photo are some slightly tender sage, and also lavenders as part of the garden suffers badly from winter wet lying close to the water table and in a frost pocket, so plants which would normally survive and are hardy, such as lavender can find the winter wet, waterlogged, soil intolerable. To be on the safe side I often bring 2/3 in for the winter. In addition, I grow some lavender in a wall creating a better micro climate for them of free draining soil away from the water table. Hardy can be a relative term depending on your garden situation.