Can Leaf Mulch Hurt Your Garlic Crop
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Can Leaf Mulch Hurt Your Garlic Crop?
Q. I put leaf mulch on my garlic after I plant it in the Fall to retain moisture and keep out weeds. My question is: when do I remove the leaf mulch? I'm worried that it will cause the garlic to rot.
----Kathy in Hopewell New Jersey
A. This question hit way too close to home for yours truly. My garlic patches—generally large portions of three or four raised beds—were trouble free for decades; and they were always mulched with shredded leaves in the fall that stayed on until the harvest in early July. But then I started having problems a few years back with some of the shoots turning skinny and tan-colored as opposed to staying lush and green. When I pulled up these 'bad shoots', I got a dead stalk with some blackened, nasty-looking fungus where it met the soil line. Sometimes there were a couple of tiny, distorted cloves attached but in many cases I had to dig down after the harvest and make sure I got all of the infected cloves out of the ground.
Now, it's important to note that I have never had a complete failure. The first year this happened (a miserably wet year), I still managed to harvest about half of what I had planted; but the loss of that many bulbs was a heart-breaking wake-up call.
So I continued to replant my own cloves—because it's 'my' garlic, and I would be devastated to lose the very distinctive strain that I've been breeding for decades. But I made sure to plant those cloves in different beds that fall. I also found a tip in an old issue of Organic Gardening magazine from when I was Editor that suggested dipping the cloves into a solution of baking soda before planting, which I did.
I recommend you do the same this Fall: make a 'slurry' of baking soda and water and let the individual cloves soak in it for five minutes or so before planting.
I did still use shredded leaf mulch and had some loss at harvest time that season, but not nearly as bad. Then I marked those beds clearly and made sure to plant the next crop in places that had been garlic free for two seasons. I also noticed that the soil in some of my beds seemed to have gotten a little 'heavy' over the years, so I mixed a lot of perlite into the new garlic beds before planting to improve the drainage.
Stuck with the shredded leaf mulch and repeated the baking soda 'slurry'. I also started dipping the cloves into a container of vodka after the baking soda—another tip from an old OG. Still had some neck rot…
And so this year (meaning last fall) I rotated to yet new beds, added more perlite and did the baking soda and vodka dip but bagged the mulch. I decided to just keep pulling out the chickweed that loves to grow between the garlic shoots.
And so far, so good; it's been a really wet season but I don't see any dead shoots—again, so far. I'm relying on my memory to tell me around what part of the season things have started to go bad in the past, and memory is the least trustworthy part of my brain. OK—and spelling. And math…And…
…And staying on track! So let's get back to Kathy with her mulched garlic in the ground before I notice another bright and shiny object.
If this is her first or second year growing garlic and/or she's had no previous problems with rot, I'd leave the mulch on. It's great for weed prevention and it attracts earthworms to the beds (and those worms are great little soil improvers!).
But one of the main benefits of mulching an 'underground' crop like garlic is to protect the bulbs from heaving out of the ground during cycles of freezing and thawing over winter. And winter is over (knock on wood), so she can certainly choose to remove the mulch and hand weed from this point forward. No matter what, she should make sure to rotate her planting areas this fall and do the baking soda and vodka dips.
Oh, and speaking of 'the dip', I should answer the obvious question: The answer is 'no'. Baking soda and vodka make a despicable mixed drink.
• If you have hard neck garlic in the ground, be sure to clip off the little budges ('scapes') that will soon appear at the top of the stalks.
• Soft or hard, harvest when the bottom third of each plant has turned brown.
• And don't let this article scare you—garlic is one of the easiest and most rewarding garden crops; so be ready to plant your cloves late this summer; right around when the kids go back to school.