When my gladioli bulbs came up the leaves were covered in rust I have sprayed them with fungus spray but it is too late to fix the problem. How do I prevent this from happening next summer? Should the bulbs be dug up each autumn?

• Rust is prevalent in warm humid weather. The fungus is spread by either wind or water and can overwinter in the soil so it is important to remove any infected plant material and burn or dispose of in the rubbish to prevent spread.
• Spray infected plants, a copper based spray is a good protectant, but sometimes a more heavy hitting fungicide is required to treat rust on plants. A fungicide will need to be applied regularly, your local garden centre or hardware store will be able to recommend a suitable spray. 
• Ensure bulbs are fed with a balanced bulb fertiliser such as Tui Bulb Food  when bulbs emerge and once flowering has stopped, this keeps them actively growing and more resistant to pests and diseases.
• Regular applications of Tui Organic Seaweed Plant Tonic helps build resistance in plants, apply 60ml mixed in a 9L watering can weekly or fortnightly in the growing season.
• Once the foliage has died down cut the foliage off at the base of the corm, dispose of the foliage, do not compost as the rust spores can overwinter in the soil or compost. Treat the bulbs with Flowers of Sulphur before storing, sulphur is a natural fungicide. 
• Gladioli can be left in the soil over winter as long as the ground is free draining does not freeze in winter and is not heavy clay. 
• You are in the winterless North so it is not necessary to lift bulbs, but to get rid of rust or to treat your corms for rust, it might be necessary for one season at least.
• Try to improve air circulation around your plants to reduce humidity and the conditions that the fungus diseases thrive in.  

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