Geraniums/Pelargoniums

I have about four plants in a window box at the moment and although pretty they've been attacked by caterpillars, bud worms and now they have rust which I discovered yesterday. So I started treatment for the rust by removing and bagging badly affected leaves and sprayed with my baking soda solution to prevent any further outbreaks. Caterpillars are now under control but as you can see bud worm is still active.

Rust, a fungal disease, is difficult to control because of the millions of spores produced are carried by wind onto other parts of the plant. These copper/red coloured spores are found on the underside of the leaves. Unfortunately Zonal Geraniums/Pelargoniums are very susceptible so I might replace them with either regal or ivy leaf types in the next few weeks, I will at least wait to see if my attempt to control this outbreak is successful.

Dipel

My geraniums in the window box under my bedroom window have been eaten by caterpillars. I've been picking them off one by one but decided to see how Dipel works. It's been available for about 30 years!

Dipel is an insecticide containing Bacillus thuringiensis bacteria, caterpillars apparently stop eating immediately once they have ingested it, taking about three days for them to die. Confidor is an alternative but too toxic for home gardener use however, it is usually the only product available at hardware stores.

Dipel spores are killed off by sunlight so it should be applied every 7 days when infestations are high.

Although it is safer to use, always wear eye protection, gloves and dust mask especially when opening sachets as spores break loose into the air. The same protection should be worn when spraying pyrethrum, dusts or organic pesticides. Packaging never provides enough information on personal protection equipment.

I now would never buy premixed trigger/spray packs for any product. I purchased PestOil (Yates) only a few days ago, I could not adjust the droplet size and it ran down my hand. More of a problem was a pyrethrum spray pack that I purchased a few years ago. The pack leaked badly, despite it being organic is too toxic for this to be acceptable.

Recipe for control of fungus

In 2 litres of water add a drop of vegetable oil, a drop of detergent, 4 teaspoons of bicarbonate of soda and spray plants every 7 days for the entire growing season. It's perfect for most fungal problems and I'm using this on my roses and tomatoes.

This a remedy from Gardening Australia.