Last fall, while visiting The Royal Agricultural Winter Fair in Toronto, I came across a very neat exhibit–it was a 38 foot mobile “greenhouse education centre“–sponsored by Naturefresh, a Leamington, Ontario based greenhouse grower of tomatoes, peppers and cucumbers.
I love growing tomatoes, and have written about it on this blog quite a bit, including here, here and here–oh, and there’s a podcast interview here–so I prettymuch flew over to the display when I realized what it was!
Greenhouse growers have to create an elaborate artificial world in order to grow tomatoes year round. It’s very different situation from that of a home gardener, but, there are some useful ideas we can borrow.
Supporting the plants
Visitors to my vegetable garden are always amazed to see my heirloom tomatoes growing 8 to 10′ tall, but that’s nothing compared to the height of a greenhouse tomato plant! In a greenhouse, as the plants grow, workers wind the stems up and around a string, which is connected to a spool. As the plants grow, the spool lets out more string, and the plants are gradually dropped down. The stems are slowly wound around the row, just like you’d coil a garden hose. The plants can end up being 30-45 feet (10-
Growing tomatoes up and around a string is also a great way for home gardeners to support tomatoes–it’s part of the system I use, as I explain in this post.
Nifty gadget available for home gardeners too
I’m always worried that the string I use to support my plants could slice into the tomato stem. I was quite excited to notice the ingenious little clips that the greenhouse growers use to run the string up the plant. It keeps the plant secure but there’s no danger of the stem getting damaged. I wondered whether these clips were easily available for home gardeners to buy and yes, I found them on Amazon!*
Tomato plants are resilient
Speaking of stems, sometimes when I prune my tomatoes, sometimes I end up damaging the stems a little. I always feel badly about this, and worry that I’m weakening the plant and that my carelessness could even kill it off. After seeing this display I’m going to stop worrying–take a look at this close-up picture of the stems on the greenhouse plants:
The outer layer of the cambium is completely split apart/missing in a lot of place. Now I’m not saying I intend to purposely inflect damage on my tomato stems, but if these greenhouse plants can have that level of damage and still keep producing, well, I don’t think I should be worrying when I nick the skin on my stems a little. The pros obviously aren’t worried about it.
Soil – don’t try this at home!
I was surprised to see that the greenhouse tomatoes are rooted in a startlingly small amount of soil/bark chips:
Now, this isn’t something you could replicate at home. I believe the only way it works is that the plants are receiving a precisely formulated mix of water and plant food through those white tubes. With such little soil, they can’t be getting nutrients from the potting mixture. No home gardener I know of has the patience or elaborate setup required to grow tomatoes like this. It was interesting to see, but not something I’ll be trying myself.
As I took a close look at the plants I could see that the growers are fastidious about pruning. Each plant has a main stem and that’s it. There are no wildly branching side shoots. just the minimum amount of green growth required to produce and sustain fruit:
This is a practice I highly recommend for home gardeners. If you don’t already know about pruning tomatoes I have a post on how to do it here.
The reason we grow tomatoes
One important aspect of the difference between greenhouse grown tomatoes and homegrown tomatoes was not on display–and that’s the difference in taste! The greenhouse tomatoes looked beautiful, and I’m sure they were tasty in their own way. But nothing beats a home grown tomato, especially when it’s one you’ve grown yourself!
But, since the outdoor tomato season is short, I’m grateful for all the work that goes on under glass year round to keep tomatoes on the menu.
And I appreciate that the Naturefresh folks created this display to explain to curious types like me how they do what they do. I believe this trailer tours around Ontario and parts of the U.S. during the warmer months. If you’d like to see it for yourself, you can check their website for its schedule.
*Disclosure: some of the links on this page are affiliate links, meaning, at no additional cost to you, I will earn a commission if you click through and make a purchase.