watering more then you normal would, is start
water retain crystals would help.

We can't water too much, as that would raise our water bill, which is very high for our area. :( We're hoping for another solution that doesn't involve more water. Any ideas? I hope someone can help.

I have two square foot beds that we installed for the first time this past spring. I had the same issue you are experiencing with the beds drying out quickly. I too laid down a weed barrier on top of my existing ground, then put the beds and new dirt on top. What we ended up doing is taking a small hay bale we had left over from our Halloween decoration last year, and I pulled the small bale apart and spread the hay around the beds. This really seemed to help keep the soil from drying out so quickly. I bet I went from watering every day to about every three or four days (100+ temps). I just enjoyed my first ever Sugar Baby Watermelon for the 4th of July and it was tasty! Also have been enjoying cherry tomatoes, roma tomatoes, and have jalepeno, habenerro, and bell peppers on the way.

Hope this info helps,
Bryan

Thanks Bryan, there's a strategy! Did you put the hay around the outside of the beds? Or around the inside of the beds?

Kendra,
Here is a pic of when we started. Until we expand our larger bed to encompass the whole side yard area, for now I just bordered it with rubber landscape edging held in place by spikes.
Setup is: everything has weed barrier under it. Native tree mulch outside of sf beds. Ladybug brand sf garden soil in raised beds, and since pic was taken, added hay/straw to help keep if from drying out. We also have a black soaker hose running under the straw that we turn on as the plants start drooping/looking a little sad.

Here is a pic of our watermelon we just picked on the 4th of July. I took up growing right under a lemon basil plant, which smells incredible when you touch it. It shows the setup we ended up with for right now with the mulch and hay combo.

This year is our first year to do a sf garden bed. We lost a squash, zuchini, and two corn plants, but I think the sf garden bed kits we bought are not tall/deep enough for those plants. Anyways, if any more questions, ask away. This is my first year doing sf gardening, so I'm all trial and error right now, so please share your pics/questions/suggestions/ect... I have some more pics of the garden to upload from the camera so I'll try and get them on here soon.

You could always consider putting a solid bottom on your bed. To be honest, evaporation is probably a more likely culprit than the existing soil in any kind of raised bed, and if you've had such little rain over the last few years then your humidity is probably ALSO really low. The previous posts recommending heavy mulching are probably your best bet to help keep your soil moist.

Another option in arid areas that is more work in the set-up but supposedly is to dig the bed in so that it is effectively below grade, so any rain that does fall concentrates in and around the bed. Mulching will slow evaporation loss and an in ground barrier around the edge of the bed could keep the surrounding soil from slurping away as much of the moisture.

I don't know how deep of a bed you need, but I built a 4X8 bed for strawberries using a technique similar to the "earthbox". I lined the bed with a sheet of plastic, layed 6 sections of 4" drainage pipe in the bottom, fixed a spout in one of the pipe to come up to the surface and filled in with organic potting mix and composted cow manure. I water about once every three weeks. The strawberries are very happy.

It wont help you this year, but maybe dig the dirt out of them end of year and place something on the bottom that is solid with just a few drain holes. Heck, even just laying a few extra layers of newspaper might help slow the water but still allow excess to drain. Also if that is real wood, might help to keep the soil off it with some plastic. I find real wood a pain due to its constant wicking of moisture from the soil.