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julzology

Is my rooftop garden too hot for my tomatoes?

julzology
13 years ago

I've never grown tomatoes before but since moving out of a condo and into an actual house, I have two plants in containers on my "porch".

I live in an attic apartment and my porch is actually the roof of the garage and covered with asphalt shingles which get quite hot. The porch is in the sun almost all day.

So far the plants seem to be doing OK. One is a Beefsteak and one is an Early Girl. The Beefsteak only has four little green tomatoes which don't seem to be making any progress. The Early Girl has 13 tomatoes at last count and lots of flowers and seems to be progressing nicely.

Hubby is diligent about watering when they get dry.

After poking around on this message board a bit I'm wondering if maybe it's too hot for them where they are. Especially the Beefsteak which doesn't seem to be growing as nicely as the Early Girl.

Any advice would be greatly appreciated.

Comments (10)

  • drtomato
    13 years ago

    "asphalt shingles which get quite hot" hahahalol where do they all come from?

    answer to your question: ......maybe?

  • nygardener
    13 years ago

    I grew tomatoes on a Boston rooftop and they did great. Keep them watered and fertilized, keep them up off the asphalt (on your wooden "porch" or a platform), and grow them each in its own big pot  10 or 20 gallons is not too big. Mine sat next just to the south of a brick chimney, which stayed warm for a couple of hours after sunset, and they were the sweetest tomatoes I've ever tasted.

  • wordwiz
    13 years ago

    In addition to what nygardener advised, I would also cover the sides of the containers with reflective materials or newspapers - anything that will help keep the dirt temps down. Maters like to keep their feet damp and warm, not soggy and hot!

    Mike

  • jerrya
    13 years ago

    You should search some of the posts about dealing with heat in places like Texas, Florida, Arizona, etc. The plant can take a good bit of heat, but, it if is too hot and humid, you will no longer get fruit set. From what I've read and experienced, if it is consistently 92 or more in the day and does not cool down for at least a few hours at night to 75 or less, you are pretty much not going to get much in the way of fruit set, though the plants will survive. IF you add high humidity to the mix, those numbers may be generous as humidity can affect the pollination process too.

    I had to grow in containers this year in Dallas and on a concrete driveway too. I determined that it was too hot and causing me problems with BER. I put up shade cloth (50% block) as well as bamboo shades to keep the roots out of direct sunlight and that helped a lot. Good luck.

  • taz6122
    13 years ago

    Asphalt shingles are also not made for constant foot traffic. You'll most likely spring a leak in no time if you're walking on them.

  • julzology
    Original Author
    13 years ago

    Thanks for your replies all. I appreciate the advice since my husband and I are just kind of winging it. The tomatoes on the Beefsteak plant haven't grown at all in several weeks and now they're starting to turn yellow. Not sure what's up with that but we're going to look for a way to get them up off the hot asphalt. It was 96 here yesterday and supposed to be at least 90 today.

    Maybe my containers are too small....not sure of the exact size but they can't be more than 2 or 3 gallon pots.

    The rooftop is over the garage so springing a leak wouldn't be catastrophic but I'm sure my mother in law doesn't want water leaking on her pristine '87 Mercury Marquis, lol. We'll have to keep an eye on that.

    And I'm not sure if we used the right fertilizer we bought some Miracle grow 19-6-12 on the advice of the guy at Home Depot who said to get something low in phosphorus.

    Live and learn I suppose. The good news is that the basil and parsley are thriving and the peppers are doing well so far too.

  • wordwiz
    13 years ago

    "Maybe my containers are too small....not sure of the exact size but they can't be more than 2 or 3 gallon pots."

    Yep, they need to be at least 5 gallon. Your plants are probably rootbound.

    "And I'm not sure if we used the right fertilizer we bought some Miracle grow 19-6-12 on the advice of the guy at Home Depot who said to get something low in phosphorus."

    I wouldn't ask his advice on how to treat a disease! IMO, MG is useless. First, tomatoes do not need a lot of nitrogen; look at Tomato-tone, probably the best tomato fert available. Its ratio is 3-4-6. MG, at least most of the types I have seen, has no calcium. Bad, bad, bad, unless you like BER. Plus phosphorus is great for roots and helping plants to bloom and set fruit.

    "Live and learn I suppose."

    How true! Next year, find a reputable garden center (If they promote MG potting mix or ferts, they probably are not a good place!).

    Mike

  • JoMac123
    10 years ago

    One year I had no problems with my tomato plants.. We got tons. Now they grow for a few days and then they stop growing and the leaves start to curl a little. Last year I thought it was too hot here in Chicago. I'm trying to think of something to raise them off the actual roof because it must be making the soil too hot. I wait all year for some good home grown tomatoes and then this happens. Does anyone have this problem? And, if you did, please give me your solution, asap.. I want TOMATOES. (weeping)

    This post was edited by JoMac123 on Wed, Jun 19, 13 at 14:45

  • Need2SeeGreen 10 (SoCal)
    10 years ago

    Well, what I do is put my pots on rocks. I got a big bag of small river rocks - they are 2 or 3 inches long max -- and I space them around the pot, maybe 3 or 4 rocks under each pot.

    As far as heat, all you need to do is get the pots off the ground. They don't need to be high. (Though that's better for your back. ; >)

    What taz6122 said is important: you've got to consider the roof first. I first started doing the rock thing b/c the building guy said that if pots sat right on the patio floor, the water that came out the bottom would heat up and create steam under them, which would damage the waterproof coating. I don't know, but I hope what I'm doing is helping. I really really don't want leaks!!!!

    Mostly I don't use saucers because they are expensive. But also, I don't know what the soil implications of saucers would be. Would like to know though. I think it might cause the salt concentration to get too high.

    Also, you could try wrapping light-colored fabric around the pot. I use butterfly clips. It doesn't look spiffy I guess, but it helps.

  • Debra Fisher
    2 years ago

    I am learning as well and found out that leaf curl is from too much water. we lost our tomatos on the black asphaltum driveway after two days of torrential downpour on them...this is in the mountains and our first time growing here in new home...