If memory serves, there was a link in FAQ, or perhaps Kieth knows the zone in the top and soil beneath that water using capillary action forms.

Imagine your plants drip line if you will as the root zone.
When water saturates that area the water collects below in a bowl shape beneath the plant, and straight down along the taproot. When it is dry in the zone of that "bowl" it needs more water.

The standard for in-ground tomato plants is at least 1 inch of water per week. Being that you are in a desert climate, you will probably need more than that. I'd recommend a regulated watering system. There are some on here (like the Earthtainers, for instance) that are quite popular & work very well. If you aren't able to afford to set them up like that (like me...), then there are many other possibilities. I container garden & grow tomatoes every year. I'm not in a desert climate, but I live in Middle TN where the summers can get quite hot with temps even in the low 100's at times. I use MG Moisture Control Mix along with containers that have good drainage and probably water mine a bit more than they need, just to be safe, letting what the soil & plant determines to be extra flow out the drainage holes. That may not work for you though.

Let me assume that for in-ground tomatoes we need 1" of water per week (please correct if this is not right for Southern California with its near desert climate.) Is it better to water 1" once per week or 1/2" twice per week? I have mulch over the ground surrounding the plants as far as the foliage goes. Each plant is contained inside 6x6 concrete steel mesh 5' high about 20" diameter. Each plant sits in a hole I made about 2' dia. and 18" deep which I filled half/half original soil and "Amend." The original soil is quite rocky and full of clay, in need of this enrichment.

Cover them with some type (inch or so) of bark/mulch (organic compost be best) & start with watering maybe 3 times a week (before sunrise), 1/2 inch each time. Preferable misted on all over, not just poured. That should be a good starting plan. You may need to vary a bit from it (more or less water and maybe some fert), but not too much for your area.

Here is a website that someone posted for growing tomatoes
that I like.
http://www.growyourtomatoes.com/
cg

Fawzi, I feel your pain. I'm in San Diego. When I used to live by the beach, the soil was rather sandy and my tomatoes required a lot of water (especially after June gloom). I'd turn on the hose to a slow flow and give each plant about five minutes 3 times a week.

For the last couple of years, I've lived about 3 miles from the coast and have soil that has a lot of clay a couple of feet down. That's been a chore to figure out how to water--you don't want it too wet but you also don't want it so dry that the surrounding soil bakes hard. My solution has been to basically dig a moat a couple of inches deep around each tomato when I plant them (about 18-24" from the stem). I fill it up with compost and use it as a mulch. When I water, I make sure to water the "moat" the most.

As for watering, I planted most of my tomatoes on 3/9 and I've been watering them once a week. I probably won't change that unless they seem grumpy or the weather really heats up. When summer hits, I'm move up to watering twice a week.

By the way, my plants are about 20" and look great. I've never planted Pruden's Purple before that plant seems to love my climate/garden.

cboy: Yea...great site. Catman's page. He has a chart used for planting times that's awesome.

Thank you all for your very useful responses. I plan today to go to the "Aqua-Flo" store to buy some nozzles for my automatic watering system. Initially (for a week,) I plan to water daily a quarter inch of water, then every other day for a week, and finally twice a week, half inch each time. I will periodically examine the condition of the plants and soil and change this routine (more or less water, fertilizer, etc.) as needed. Again, thanks... Fawzi

Does anybody have any experience with using hot hose water to help warm up the soil for tomatoes?

fawzi_p

I don't know how it would work for you, but a lot of people determine if their tomato plants need watering by sticking a finger into the soil. If it is dry two knuckles down, it's time to water. You can get stable moisture around your plants by mulching them heavily, over your irrigation, and then every 2-3 days make a hole in the mulch and check for moisture.

It's the surest way to determine if your plants need watering rather than trying to figure if watering every two or every three days is best. Also, your plants will tell you a lot about when they need watering. If they begin to grow limp, it's time to water. So while a schedule is okay, it isn't the only way to ensure that your plants get the water they need. Depends on your situation and how much direct attention you can pay to them.