The roots at the base take up most of the moisture. I find it best to mulch the young plants in 4-6 inches of straw, when they are young. The straw shades the ground and helps beat back weeds and helps retain moisture. We like to make the straw beds a few feet wide. We irrigate using rainbird sprinklers on tall tripods, so the entire plant gets water. Squash are major nutrient hogs. They don't do well in poorer soils. We use chicken manure exclusively. We probably grew over 1000 pounds of squash last year and this year's crop is looking fine, despite the sobering drought and heat.
Thanks, Fred. Normally my squash do just fine, but this year it's pretty sad. Started out great but then the heat and drought hit and everything is struggling, I will mulch around the base of the plants and see if that helps.