Not sure about sand + clay -- I have heard it makes a cement-like soil structure, but I have also read that this is a myth. I think gravel or stones would be better in terms of maximizing drainage though. Biggest killer for Gaillardia is waterlogged winter soil. I have yet to lose one in my clay soil, but all clays are not created equally. Some drain reasonably well, some do not. I would test this first by putting some water in a 1ft by 1ft hole twice and see how long it takes the water to leave the hole completely the second time. If it is > 1 hr., you have problematic drainage. Compost will improve the soil structure and aerate the soil and will improve drainage over time if mixed in with the existing soil. Also, make sure you don't have the crowns of the plants too low in the soil such that water pools around them. Never fertilize them either -- they hate it. One anecdotal reason given for Gallardia's lack of staying power is that they flower themselves to death -- expending all their resources to flower prolifically right through the first frost instead of conserving energy to survive winter. There is no science behind this, just speculation. But, you may want to try cutting your Gaillardia back significantly in early fall, about 4-6 weeks before your first frost to force it to devote energy to strengthening itself to survive winter instead of flowering. This post was edited by mistascott on Wed, May 15, 13 at 11:59

I had some Gaillardia that I planted for the solstice in Dec. It germinated the 1st wk of Jan. I was worried about it during the 19 degree nights we have had, but ive just kept the top on and left it near the bricks that get the afternoon sun (they hold heat overnight). It has done fine. I was REALLY surprised when I saw that it had sprouted, but dah, it was in the sun and we had 50 and 60 degree days. Rookie mistake :-) Since then, I have researched, and I now have a better understanding of hardy vs tender, etc. Also I have moved the "ghetto" to complete shade, for now. Nothing new has germinated since. In my very Rookie experience, the gaillardia seedlings can handle cold, with normal protection. Here is a link that might be useful: Gaillardia Seedlings, bottom right pot

What I would do then is just cut down to that dense foliage (removing all flowerheads and buds), especially given you are in Zone 5 and your first frost will probably be earlier than ours here in Zone 7. Unfortunately, you do give up some late-season flowering to get a plant with a better shot at making it through winter. The other option is to leave them be and take your chances. If you lose plants, you should still get plenty of seedlings in Spring, though Gaillardia cultivars such as 'Arizona Apricot' do not tend to come true from seed (from what I have read/seen on here). Also, keep in mind that just because you have clay doesn't mean it isn't well-drained soil. If it is amended nicely and/or isn't compacted, it may drain just fine. Some clays (like mine) are literally like potting clay -- you can pour water in a hole and it is still there hours later. Others drain pretty well. Good luck!

I bought 3 (my limit--3 strikes and you're out) over the past several years. One didn't even make it through the hot July. Not one returned. I even coddled and paid attention to watering--not my usual style. To make matters worse, my last few years have been unusually dry, especially in spring. Last year not one of my regular old green Jacob's Ladder made an appearance. Fortunately, I still had seeds and have a few healthy plants to add to the garden. Variegated demands rich, damp soil. If you don't have it, the plant will die.