I don't live in Vegas, but I don't recommend your plan. The lack of humidity and the intensity of the sun are going to be an issue. I would plant them into larger pots......don't allow your plants to get root bound. Then, start them in the shade a few hours a day and over the period of a week or two acclimate them to the outdoor conditions. THEN plant them in the ground and water deep.....not directly under the plant, but in a circle just outside of the canopy. Making them reach just a bit for water will encourage root growth and help them catch up on size a bit. Honestly....this should have been done much earlier in the season so your harvest will not be great, but something is always better than nothing.