humdity and heat

[ronsmith100]

I am reading so much about tomatoes theses days. I am surely hooked.

Anyway I wanted to find a tomato that would do well in my area in my heat. It was suggested I try Super Sioux and Mexico. So I've got them going. But I am still not clear on what "hot weather" means to a tomato in different parts of the continent. The heat of say Georgia can get high but it simply cannot be the same kind of heat as in the mountains with low low humidity. For example when it is 107 here I think the tomatoes find it hard to handle the blistering radiance of high altitude thin dry air. Transpiration is off the charts up here too.

Any high altitude desert-like tomato people here?

I'm near Kanab, UT
5500 ft

[brismith70]

I am a low high altitude desert-like tomato person. I live in the Phoenix metro area. We get the same temperatures and the same low humidity. The only thing different is that you have the thinner air.

I am relatively new to the desert. I have only lived in Arizona for four years now. I have only been gardening for three of those four years. Because of the weather here, that has given me six growing seasons. I don't really try to nurse anything through the summer and I just start over again in mid to late August. I pull out the fall plants at the end of December and start over again. I have done a lot of experimentation with different growing methods and plants.

As far as tomatoes go, I have a few experiments that have been extremely successful. I have grown Black Cherry tomatoes for several seasons now with relative ease. I am also growing Red Zebra tomatoes this season. The Red Zebras are a little bit bigger than the typical cherry tomato. I am also growing a hybrid from Burpee called Heatwave Hybrid II as an experiment this year. I have grown the traditional hybrids as well: Celebrity, Better Boy and Early Girl.

I have also been able to glean a little information from some of our southern brothers and sisters. The recommendations that I have received for heirloom varieties are: Neves Azorean Red, Berkeley Tie Dye Pink and Indian Stripe. I have also been recommended a hybrid called Big Beef.

As far as growing techniques, I intensively plant because there is little humidity to worry about the spread of bacterial and fungal diseases. I water twice a day with a drip irrigation system for 15 minutes each time. In mid-June through the end of July, I use a 40% shade cloth to nurse my plants through as much of July and August as they can stand. I also experiment with planting in containers so I can move them to areas of my yard where they can get some afternoon shade. Last spring, I built an EarthTainer. which is a self-watering container designed by Ray Newstead (AKA Raybo here on Tomatoville). It worked well, but I did not put the plastic cover on top to prevent evaporation and my plants did not do so well. I am going to be building several of his new design, the EarthTainer III and experiment some more with them beginning with this fall's planting.

So, after all of this, my advice would be to experiment as much as you can to see what results you can get. Some times traditional advice doesn't always work. Sometimes there are ways around the things that other people see as shortcomings or faults of particular plants or methods. Just keep trying different things until you get it right.

[kevinrs]

As far as I can tell, desert heat isn't quite as bad for tomatoes as humid heat. The increased transpiration means the plants are cooling themselves by evaporation.
About altitude, searching keeps getting different numbers, but one reference says 4% more sun intensity per 1000 feet in altitude.

So long as the plants aren't getting stressed by it, more sun and dryer air would be better, the transpiration is what brings nutrients up the plant to the leaves, where the sunlight is turned into sugars. Making sure the plants don't dry out, and have a stable level of moisture available would be the most important thing.

I've seen a volunteer tomato plant near a leaky faucet, without support get to about 4+ feet high, and 6+ feet across, in relatively sandy, infertile desert soil, nothing added but the water. This is at near 3000 feet, dry, and temps occasionally get to 110+

[Stepheninky]

I am in the humid south and agree with what most have posted about the major difference being the humidity. Planting closer together will help the plants shade each other and shade the ground keeping the roots from getting as hot would be a benefit in your dry climate. I would recommend using white plastic or mylar as well as it will hold in the grounds moister and also help keep the roots from getting too hot.

Another difference is you will want to plant your seedlings deep. (we do that here as well and for us it works better than the trench method.) I think in cooler, wetter areas trenching is probably fine. but in hot climates where the top of the ground tends to dry out or crack at the surface planting deeper helps protect the roots and puts them down far enough that the roots can pull some moister up from the deeper soil.

Anyways hope that is of some help

[ronsmith100]

Interesting

Some agree with humidity altitude difference and others dont. Of course I cannot agree or disagree because I'm a 'mato rookie. But I will keep looking for ideas.
I have already set up a two a day drip system. I will also do a solar radiation net later in the blistering part of the year. And most importantly I hope to set a standard for Southwestern Stepps tomato growing!

Gimme rice vinegar, salt, and a slice of it. OMG

And

My Legends before August are crazy good!

[b54red]

I know we don't have your dry air; but we frequently wish we did. Last year from July til early October we had some unusually hot weather with almost no rain. I think one thing that will help more than anything else is giving the plants sufficient water. Drip irrigation twice a day for only 15 minutes would have been totally inadequate last year. During those really dry months I would run mine for at least an hour and a half every other day and sometimes for much longer. Many of my plants kept setting fruit even with temps hovering around 100 and humidity of around 90%. I'm no scientist but it only seems sensible that a plant would be giving off huge amounts of water in those high temperatures and probably even more so in your arid conditions. If the plant doesn't have enough water then it will naturally be stressed and not set much fruit. I always try to give the plants a very heavy watering at least once a week and really soak the ground, besides the regular watering that they receive during times of extreme heat. I also like to cut off some of the growth tips so there are less blossoms and stems needing the water and more of the plant energy can go into fruit production; but that might be counter productive in an arid region. I have also found a good shot of Miracle Grow every 3 weeks or so can be a big help during those really hot weeks. It also seems to be a big help to apply a very thick mulch to retain moisture and keep the soil cooler. I usually use hay or grass clippings but this year I am trying cypress mulch and it seems to do a better job of keeping in the moisture so the need for watering may be less frequent this year.

Besides adding organic matter to the soil to help hold moisture I always add some water crystals to the top 4 or 5 inches each year. They really help in maintaining a more even moisture level in the soil and save a lot on water. They actually are a big help when heavy rains happen because they absorb and hold much of the excess water until it is needed and keep the soil from becoming so muddy when 2 or 3 inches fall in a day or so.

I grew Heatwave hybrid several years ago and I hope the Heatwave II is a big improvement. The best tomato in the heat last year was one I call Bill's Berkley Pink; but I do not know if it is a stable plant or not. I sent out seeds to a fair number of people and hope to hear how it is doing this year. Of the well known tomatoes I agree about Indian Stripe, BTDP, and NAR. I would add a couple more like JDs Special C Tex, Old Virginia, and Gary O' Sena. Far and away the tomato that does the best for me in the hottest part of the summer is Big Beef. The fruit are not as large nor as abundant during the worst of the heat but at least it keeps right on putting out decent toms when most others have just quit.