Tomatoes and aphids - well, aphids in general

A reader writes: "Bunnings girl - my tomatoes have aphids. What do I do?" and I replied something along the lines of "I'll write with a long email / blog post about it". Hey it's 2008 and recycling's all the go, right? So there's nothing wrong with taking an sms conversation and blogging...

In 2000 I did an honours degree in chemistry working on roses in pots, and because of what I was doing with them (over watering and over fertilising them) aphids were a huge problem. I wasn't about to use chemicals on these things when I spent 10 months in a greenhouse with them (I'm sensitive to chemicals as it is, and was especially then, and didn't want to make it worse!) so I used a good natural approach to aphid control.

Nightshade spray (so - tomatoes, eggplants, potatoes etc)
These fabulous plants have alkaloids in their leaves and you can extract them in a solvent (like water) quite easily. As it's the plant's natural defence, it tends to ward off the bad bugs and not affect the good ones.

This spray keeps for about a month before the effectiveness wears off, if you keep it in the fridge.

• 1-2 cups nightshade leaves (loosely packed), chopped up
• 1-2 cups boiled and cooled water
• Spray bottle
• Extra boiled and cooled water

Put the leaves in a jar and cover with water. Steep overnight. Strain well, and put in the spray bottle and add the same volume again of water. Shake and spray onto the leaves where you see the aphids - under leaves for eg.

Some people are allergic to nightshades (my sister for eg!) so be careful about labelling this!!