Pruning Tomatoes

Kerry has about a dozen Tomatoes growing in pots outside the laundry. These are all strays I brought home, no label, overgrown, falling over, last pots out of a tray. A bit of a lucky dip.
Anyway the boss is very proud of her Tomatoes. She does all the things I warn against; recycles potting mix with some soil and chook manure, grows vegies in the narrow, shady strip on the East side of the house, loves growing stuff in cardboard fruit boxes. Best of all she loves showing me how well they’re doing and of course that’s exactly what they are doing right now. Not all straggly as I feared growing in such a shady environment, flowers developing nicely but I did notice one thing…
These are going to be big plants and they are growing in relatively small pots. Actually 12” (300mm) Pots. Now keep in mind, Kerry has put trellis along the fence to support her Tomatoes. Where does all the nutrient and water come from to support this such big plants? Especially once fruit starts to set in high summer we will be watering every day (yes we have tanks) but I’m sure you can see the drawback to growing tomatoes in pots.
So what to do? Prune the plant. Tomatoes grow in a wonderfully rampant fashion. At the axil (the angle where each leaf grows away from the stem) a new shoot develops. Very quickly it’s difficult to tell which is the main stem because each shoot continues to do the same thing and produce more shoots. Very sorcerer’s apprentice! In no time the plant becomes a matted, tangled, dark mess with a massive appetite. (For additional images, please follow this link)

I spent a lazy half hour last weekend just rubbing the emerging shoots out of the Tomatoes and I cut out a few larger ones with a sharp knife. I have left 4-5 stems per plant and will need to go back again this week to give them a quick check. 4-5 stems is manageable and focuses the plant’s energy. While I was pruning I tidied up their “skirts”, the old leaves dragging in the dirt around the soil level. These leaves were turning yellow and scrappy and a couple of plants looked like they had been dusted with flour (powdery mildew). I am hoping that removing these old leaves will control the mildew by allowing light and air in. That will save using any chemicals. If you have any other suggestions for controlling powdery mildew without chemicals please let me know.