What about weeds from hay mulch?

A lot of on-line gardening resources recommend using straw rather than hay for mulch in a garden because of potential weed problems.  I wanted to say a word about that.

Hay growing.  June, 2008

 "Straw" is what is left when the seed head is removed from grains.   So, there is oat straw, wheat straw, barley straw, etc.   Maine doesn't grow much grain, although some determined folks are trying to address that, which is good.   Maine does grow a lot of hay, and people have been using hay in their gardens here for a long time.

Straw may contain seeds from the grain crop or weeds, but there usually should not be much.

"Hay" may include very little seed or a lot, or something in between.   Hay can be made up of very few plant species or many, depending on the type of hay, how it was managed, the time of year it was cut, and the field or even the part of the field from which the hay came.

Hay is usually less expensive than straw in Maine, at least when bought from the farm.

If a good, very deep hay mulch is used in a garden, it will smother most weeds.   I used a deep hay mulch in a garden I kept years ago, because it reduced the amount of time I spent weeding.

Not all hay is the same in terms of seed load.   If you are looking ahead to the day you might remove the mulch and want to garden without it, or turn over the ground in a wide area, then it makes sense to pay attention to the seed load in the particular hay being purchased.

Hay cut very early in Maine, such as in May, will usually have relatively little seed.   The seed hasn't had the opportunity to mature yet.   All other things being equal, May hay is often also higher in protein and more expensive because of its value for feed.   But, it still may be less expensive than straw, and is likely to be locally grown.

The earlier a "first cut" (first cut of the year) occurs in a given year, the lower the seed load.   A good "second cut" from the fall will also likely be lower in seeds.   Less second cut is available than first cut, because some acreage is only hayed once a year.   Second cut hay tends to be more expensive than first cut unless it is being sold as mulch hay.

If you talk to the local person who actually grew the hay, then he or she can tell you approximately when the hay was cut.    If a lot of people in an area brought in first cut hay late in a given year, so you can't find earlier cut hay, it is likely because weather conditions did not allow an earlier cut that year.

Hay is a standard garden mulch in Maine, and it can work well.   Expect to pay a bit more attention to it than to very clean straw, but expect to buy local and pay less.     

In the garden, add more hay mulch to thin spots when you notice them, such as where a weed pokes through, and add a new thick layer of mulch in the spring.  

Note:  we sell hay, although mostly feed rather than mulch hay.   Some of the mulch hay is bought by folks with gardens.   Fun reading:  "Ruth Stout's System", Mother Earth News (2004).