Question
I have two rose bushes in pots on my terrace, when the weather became humid one day, both the plants became infected by white mould on the leaves and flowers. I treated them with a product recommended by the local garden centre. Over the next two days the leaves started to fall off, but not the flowers. The bushes did not look good without leaves so I cut them back. This was in May. I live in Mallorca, Spain. Although this is not the right time to prune roses, they are starting to sprout leaves again. Will I get another crop of roses this year? or shall I give up and buy another type of plant more hardy from humidity,or do you recommend that I persevere with the ones I already have?

Answer
It sounds like you have ideal weather conditions for rose mildew. Also roses that are planted close to a wall or close to other roses are also at risk. This is a fungus which burns the leaves if you don't kill it quickly. It is a very common occurrence in humid weather so all roses will get it. If you enjoy the roses, just spray them with what the garden centre recommended as it will kill the fungus spores. Make sure you also spray the canes and around the base of the rose bush.  Cutting them back will only delay the bloom period but it will take about another three weeks to a month for them to flower again. Don't be concerned about cutting the roses. You can prune roses anytime of the year except in the fall. Many gardeners keep vigorous roses under control by pruning them back in the summer. Because a specific mildew spore lives on the rose leaves, most roses will have some problem with the disease when the weather gets hot and humid. The only class of roses that I know of which seldom gets mildew are the Hybrid Musks. The modern hybrid teas are the most prone.