Growing tomatoes on the roof?

[MamaRoo]

Sounds odd, I know, but I'm in the northwest, and my house is surrounded by trees. The front yard gets some morning sun, but it's gone by 10:30 or so. The back of the backyard gets sun around 10:30, but also gets shaded from the trees pretty early. My deck gets the latest sun starting around 11, but lasting until a couple hours before sunset.

I have a South facing roof on my sunroom-in-progress that gets some early morning sun, will get sun until late in the day, and has a black surface so it's likely to be warmer than any other area around my house. The pitch is not steep and nothing would slide. I already grow my tomatoes in pots so I can move them around the yard, and I was curious what y'all would think of putting them on the roof....

 

[flgardengirl]

I don't see why it wouldn't work if you had a really safe way to get up there and water them etc. There is a guy on one of my garden forums that has a whole roof garden in NY. It is really quite amazing.He gets less pests up there for some reason too.

 

[SweetSilver]

We did this on our laundry-room roof, which had a shed roof, when we lived in Seattle. The tomatoes were a bust, it got so hot, but it wasn't a total loss.

Here's what worked. We put compost and soil in big, 5-gallon pots and placed those in a turned-over lid of a plastic trash can (as pro gardeners, we use a lot of 35-gal "buckets" and these lids often come with them). The tomatoes, like I said, were a bust on the black tar roof. Maybe you could lay down another surface? Also a bust: eggplant, pumpkins. BUUUUUUT, peppers were glorious. We grew some very nice anaheim-style peppers and some jalapenos. Still not as spicy as the Yakima Valley, but still very nice. AAAAAAND.... carrots! These were by accident, from the compost where we tossed the carrots that had gone to seed (such pretty flowers!) Huge carrots, no tunneling by worms--fabulous. These grew happily in the same pots as the peppers.

Watch out for the weight of the pots. The soil is wet, they are very heavy, so you want to be cautious about how many. We put up 7 pots.

Good luck!

 

[wyoDreamer]

I would be afraid that the intense heat put up by a black roof in summer would cook the plants. I have helped family members do roof work a time or two and boy, that is miserable up there on a sunny day.
Two years ago, I had some potted tomato starts that were ready to go outside and put them into a soda flat that I had lined with the thick black plastic contractor garbage bag to make it water tight. I set it outside to let the plants harden off. The plants died, even though I kept them watered. It was just too hot with the black plastic, the roots never dried out I made sure of that, but the leaves and stems turned black and dried out. I have had the same thing happen since when a tomato plant tipped over in the wind and the top leaves laid on a piece of black plastic lanscape fabric for a day.

 

[rikithemonk]

It depends on your area and how hot your roof gets. Self watering containers will help and they are fairly easy to make. This would put a water reservoir between the plants root structure and your roof. It should help buffer things somewhat.

Tip: The larger the wicking tube, the wetter the soil stays.

Riki

 

[SweetSilver]

The thing about tomatoes is not the intense heat of the day so much as warm nights in a addition to warm days. This is more the reason that tomatoes thrive in greenhouses than the daytime temperature (though it helps, for sure). Here in the PNW, we just do not have the sustained, sultry nights that tomatoes love. Sunny spots help, for sure, but finding a way to raise the nighttime temperatures will bring more success than putting them on the roof.

 

[MamaRoo]

The thing about tomatoes is not the intense heat of the day so much as warm nights in a addition to warm days. This is more the reason that tomatoes thrive in greenhouses than the daytime temperature (though it helps, for sure). Here in the PNW, we just do not have the sustained, sultry nights that tomatoes love. Sunny spots help, for sure, but finding a way to raise the nighttime temperatures will bring more success than putting them on the roof.

This is good to know. I have them on the deck, next to the house, so they get the heat that was absorbed by the siding. Maybe I can come up with some sort of solar wall using plastic bags filled with water and black covering.