Are you using the sand to mix in with small seeds so that when you scatter them you don't end up with everything all clumped together? If that's what you're doing, then the amount of sand you want would depend on how closely spaced you want your plants to be...more sand will space the seeds farther apart, less sand they'll end up closer together. I would think typically you'd want a decent amount more sand than seed, otherwise the seeds will end up almost as close together as they would without the sand. I don't know where the 1 part soil comes from, but the 9 parts sand to 1 part seeds sounds like it might be reasonable.
I found that even though nine parts sand to one part seeds sounds like a lot, I had to double it in order to get the seeds spread far enough apart. I was hesitant at first but as I proceeded it was really a lot of fun. Not only could you see where the sand is but you can also see the seeds. Of course it is not raining now and I wanted to make sure the seeds have a nice start, so I misted them from a garden sprayer twice.
These annual wildflowers are coming up quickly. I am thinking about purchasing a couple of the California Native Annual Wildflower Mixes from Theodore Payne Native Plant website. I always have a lot of space between perennials that I am trying to start in the garden and my wife suggested that for a season or two, it might not be such a bad idea to sow native wildflower seeds. There is a large selection at the website and it sounds like a fun thing to do. Even if I end up weeding their offspring next year, this might not be such a bad idea to fill in the awkward spaces. I have used a lot of Red Devil Verbena to fill in so far but I am always looking for something new as there is a lot of space between some of the perennials!!!
I can hardly wait until some of the first wildflowers start blooming and I can photograph them.
hi---ninety percent sand wouldnt be too much but must be dry---you can always go back and scatter the leftover sand out a second time---concerning sand for seed planting--as a soil ammendment in loam i cant remember what proportions but like one quarter to half sand and the rest loam will make concrete hard dirt as i found out --stevo
I don't think this sand was an amendment--it's just a way to sow your seeds so they don't wind up all on top of each other. If you mix your seeds witha bunch of sand and then toss them out on the ground, you end up with much better spacing between plants than you would if you just tossed the seed out there. But there's nowhere near enough sand to cause the problems you will have if you try to amend clay with sand.