Smells Like Coffee?

Joel planted lettuce seedlings in one of our hoophouses yesterday and the place smells like.....coffee? Last year's lettuce crop in the hoophouse was seriously damaged by wireworms. These are small, stiff, yellow grubs, the larva of the click beetle, that burrow into the stem of the plant and eat it out from the inside. All you see is a suddenly totally wilted, dying lettuce. If you pull it up and check the soil right around the stem you can sometimes find the culprit and dispatch it. We had been unable to find a successful organic solution for the pest until we talked to our friend who brought us all those potatoes a while back. Seems he was gathering up coffee grounds from a number of local restaurants as something to add humus to his soil. But as he grows several acres of potatoes he never had enough coffee grounds to treat the whole place. He noticed that he had no wireworm damage to his potatoes in the places where he had put the coffee grounds. Potatoes are another crop that we have had a lot of wireworm trouble with, so we are trying it, first on this lettuce bed and hopefully next spring on some potato plantings if we can gather up enough grounds by then.