Sunday, July 23, 2017

Herbicide Contamination Update

This is a great 'carrot-year' for us! Just in time to help loosen Bella (5) and Adri's (6) baby-teeth.

Hello Folks! The gardens are finally really thriving this year! We've put the 'herbicide contamination debacle' behind us and are thrilled to already be eating cucumbers, potatoes, summer squash, and tomatoes daily from the gardens. That's early for us! Both our local Food Pantries have begun receiving weekly deliveries of fresh, organic produce that, along with cucumbers and squash include cabbage, beets, carrots, kale, elephant garlic and lettuce.

We feel relatively confident that we have identified the source of the herbicide contamination that devastated so many of our seedlings this year. We had made our own potting-soil from a combination of composted horse-manure combined with last-year's compost (made primarily from leaves, grass-clippings, wheat-straw and vegetable scraps) and we weren't sure which ingredient was the cause of our problems. LINK to original article

We make our compost primarily from leaves, lawn clippings, wheat-straw and food-scraps.
We are reasonably certain that the horse manure was to blame. We have a friend who brings us his composted horse manure which we have used all throughout our gardens for several years with no ill effects. He has always been very careful to bring us loads from a pile that has sit fallow for many, many years. Coincidentally, the one time he brought us a load that was from a fresher pile was the load we used to mix up all our potting soil (at least 15, five-gallon buckets!).

Herbicide contamination of tomato.
The only places we've noticed the stunting effects of the herbicide were 1) in plants grown in the potting soil we made, 2) places where we dumped the potting soil in our greenhouses,  3) where we used that batch of manure to amend soil directly. None of the places that we have used the wheat straw as mulch, or the compost we made from it have shown signs of contamination  -- unless we also used the manure in those same spots.

Our last piece of evidence that supports our theory is that our friend used some of that less-composted manure on his tomato patch and all of his tomatoes are showing strong signs of contamination (and he didn't use any of our compost, or the wheat straw we thought might be the source).

It's becoming harder and harder to find clean sources of material to use as mulch, or to build our compost piles as more and more chemicals are being used to grow food, and showing up in the environment from other sources. This herbicide contamination was a real wake-up call for us!

Will we continue to use the horse manure from our friend? We've really meditated on this. It is our intention to demonstrate a "veganic" style of agriculture that uses no livestock manures, or commercial, concentrated fertilizers. It is important to us to use local materials - like leaves and grass-clippings to create soil-fertility. We don't eat meat of any kind and feel it's hypocritical to benefit from the by-products of an industry that is not sustainable and that we don't support philosophically. Recently we did turn down an offer for a load of goat-manure to be delivered to the gardens, for these reasons. We only used a 2-pound box of commercial fertilizer to get all our seedlings started this year, which is incredible when you realize how many hundreds of seedlings we started!

A pile of our finished compost - super-food for the gardens!
For now though, we're going to continue to accept Dave's donations of horse manure. Because he saw the effects of the contamination on his own plants, we're confident that he'll only bring us manure that is thoroughly composted. With the exception of the single contaminated load, Dave's been bringing us manure that's been composting for 20-years. We don't know how much nitrogen or other nutrients are left in it, but the composted manure has a beautiful consistency that really helps "fluff" our soil which has a high clay content. Maybe when Dave runs out of manure that's sit fallow for a long time, we'll wean ourselves off this source of soil-amendment.

Note: If you are using horse manure in your own gardens, be sure it has composted for a minimum of two years but the longer the better. Also, if the pile sits out in the rain and fresh manure is added on the top, it's possible that the rain can leach the chemicals down into the older material at the bottom. If in doubt, do not  add it to your garden, or use it to start seedlings until you test it. One website we visited recommended testing the manure/soil by planting peas or beans in it which are highly susceptible to contamination and will show signs of leaf-curling once the second set of leaves begin to form.

First ripe tomatoes - July 7th!
We're happy to report that, thanks to 'volunteer' tomato seedlings that we transplanted into our greenhouses, and Steve Rose's generous donation of surplus 'starts' that we have close to 100 tomato plants growing and the first Stupice plants began producing ripe fruit in early July - right around the normal time for our greenhouse plants!
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