I answered a question on another forum about grass and weed seeds. I know there aren’t many seed planters in Texas but some others from out of state might find this interesting reading.
There is a huge misunderstanding about the percentages listed on seed packages. Actually huge is an understatement and misunderstanding is putting it mildly. It’s more like false advertising because the typical homeowner consumer cannot know what s/he’s buying. Here’s why: Seeds are sold by weight, not count. When you see a bag that is 90% clover and 10% bermuda, you expect to have a clover lawn with a little bermuda mixed in, right? The problem with that is that clover seed is very heavy and bermuda is very light. A pound of clover has 150,000 seeds while a pound of bermuda has 2,100,000 seeds. When you do the multiplication, you find that one pound of seed will have 135,000 clover seeds and 210,000 bermuda seeds. This means the seed is actually 61% bermuda grass seed when you count all the seeds. I don’t think there is a clover/bermuda mix like this, but it served as a good example of the problem with buying seed. The issue is even bigger with extremely light seeds like bent (6,000,000 per pound).
Here’s another example. Since I was in Wal*Mart today, I thought I'd check out the seeds. I found a bag of bare spot patch seeds and wrote down the analysis to show what can happen to the unsuspecting gardener. This is scary. Here's the analysis from the bag.
44% Rye
38% Tall Fescue
9% Bermuda
1% other crop
0.5% weed
That is the analysis measured by weight. Here's the analysis converted to actual seed count. First you need to know the weight per pound of the different seeds.
Rye has 225,000 seeds per pound
Fescue has 230,000
Bermuda has 2,100,000
and we'll use bent again since it has so many seeds. Bent has 6,000,000 seeds per pound.
After you run the multiplication you get these numbers for actual seeds
Rye 99,000
Fescue 87,400
Bermuda 189,000
Bent (weed) 30,000
Here it is converted from % weight into % of the seed count.
Bermuda 47%
Rye 24%
Fescue 22%
Bent 7%
So that bag of bare spot patch repair is basically half bermudagrass seed.
_________________ David Hall Moderator Dirt Doctor Lawns Forum
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