Try to keep fallen fruit off of your lawn, rotting fruits encourage pests and diseases.
Check your plants for diseases like blackspot and powdery mildew, if you find signs of infection, take measures.
Check last years potato beds for any left over potatoes, remove them to prevent the spread of
Remember that, even now, it is very important to constantly check your greenhouse plants for diseases and pests.
Keep looking out for damage on your plants caused by diseases or insects and take actions to control the problem.