Mary, Over the last decade, I've used several different weights, purchasing increasingly heavier weight material each time as our late frosts/freezes hang on later and later and later every year it seems.

For a long time Agribon-19, which gives up to 4 degrees of protection was the one I used most often, and I would use two layers of it on a night when I thought 4 degrees wouldn't be enough. I had a smaller piece of a no-name brand that gave 6-8 degrees of protection and I saved it for the most tender vegetation --- usually tomatoes or peppers.

I have become increasingly frustrated with late freezes and frosts occurring through the end of the first week in May every year since 2007 (except for 2012), although our average last frost date is March 29th, so I have become increasingly reliant up frost blankets to allow me to plant early, or at least on time, without losing plants to late cold weather. Searching for the best frost blankets I could find, I found Dewitt 3.0 oz. Thermal Blanket row covers, which of course have become my favorite as they give a minimum of 10 degrees of protection. I've had them protect warm-season plants at temperatures as low as 18 degrees, although it also depends on the location of the plant within the garden.

If I combine the 3.0 fabric with 5-gallon buckets filled with water to absorb heat during the day and release it at night, I can keep tomato plants not only alive, but growing and setting fruit, even if the nights are dipping into the upper teens. This year I harvested 7 or 8 tomatoes before the end of April, and then we had our last frost/freeze the first week in May. Obviously I wouldn't be able to get ripe tomatoes before the last frost/freeze without the row covers. It has changed how I garden.

Because my area, like yours (though yours probably is even more drought-prone than mine) seems increasingly prone to spring and summer drought, irrigation is a major expense. So, the earlier I plant, the earlier I harvest, and the less I "have to" water.

Some years, when drought is very severe, I just close the garden gate at some point, stop watering, and walk away from the garden. I hate having to do that, but there's only so much I am willing to water. If we hadn't gotten rain in June of this year when we did, I would have let the drought have the garden. There's a point where you're spending more to water than you're getting in harvest, so it is, financially, a losing proposition. Getting an early start can prevent the garden from being a money-loser, and that's why I invest in row covers.

Right now, in the barn I have a lot of 3.0 (two big rolls) oz, a moderate amount of 2.0, and the now-torn and shredded remains of what once was a 500' row of Agribon-19. That reminds me that the other advantage of the very heavy frost blanket is that it doesn't rip and tear easily like the lightweight ones do. Granted, my Agribon-19 must be 5 or 6 years old if not older, but it is on its last legs. The only advantage to the lightweight floating row covers is how easily it floats, and also that it allows for more light transmission. I doubt I'll ever buy the really lightweight stuff again unless I want to use it as an insect barrier in summertime because it rips, tears and shreds so easily. Some people only use their Agribon-19 for 1 or 2 seasons, but I tape up the rips and tears with white duct tape and try to make it last as many years as possible.

Because the 3.0 oz. is so heavy, I only use it over support hoops made from PVC pipe or EMT conduit. I like to keep a good air space between the heavy fabric and the plants. Otherwise, if the outside air temp heats up quickly once the sun rises, the plants can roast underneath the 3.0 oz. fabric....and I learned that the hard way.

I bought my DeWitt 3.0 oz. fabric from Agriculturalsolutions.com.

How important is the DeWItt 3.0 oz. fabric to me? One year I used it to protect both sweet corn and Irish potatoes that were knee-high or a little taller when we had our last freezing night. It would have been devastating to have those freeze back to the ground once they already were that tall. I have no intention of ever gardening again without my 3.0 frost blanket sitting in the barn ready to go. Just knowing that I can plant when the soil temps and air temps are right and not have to wait another month or two for the inevitable ridiculously late last freeze makes gardening so less stressful.

Dawn

Here is a link that might be useful: DeWitt 3.0 Thermal Frost Blanket

Thanks, Dawn.

You're welcome.