Larry, a fellow on a gardening forum just had a similar problem with one of his raised beds of garlic, and attributed it to "white rot". Do you know what did this to your garlic?
The only thing I can attribute it to s too much water. Last year , I am to blame, as I figured when bulbing, they would require more watering than usual. So, I watered more frequently, not realizing there may have been a drainage issue, as I never had this problem for the past 10 years prior.
The reason im blaming the drainage , is because I have a bed literally 1 -2 feet over from this one. It is a larger raised ( Stone border) and I actually put a 10 inch wood raised bed on top of the stone raised bed ( to raise it more, and kinda have more control over the soil fertilizer per crop). So basically, the second raised bed is almost 1 1/2 feet over ground level, compared to the first one ( the one with the issue) which is about 8 - 10 inches raised. They both receive the same amount of sun, both have basically the same soil mixture ( although last year I added a significant amount of sand to the one with the problem hoping that would fix it). Both have the same garlic varieties from the same vendor planted at the same time. Watering and fertilizer are the same, along with the same mulch.
This year I watered sparingly, but last week we got like 3 inches of rain in 2 days. A few days after that is when my garlic started showing its symptoms. Increased yellowing/ browning of the lower leaves ( when compared to the adjacent bed which look healthy, and still have about a month to go).
Last year I didnt know what was going on so I waited longer, when if pulled them out, many of them were just rotten, and the stalk easily separated from the bulb. This year, having aa good idea of what was going on, I acted early to salvage what I could. Still had a slightly slimy outer layer, small cloves, small bulbs. Splitting at the bottom with a little brownish rot. When I peeled away the outer layers ( which were whitish yellow and soft compared to the usual our white and firm, the cloves looked fine, but with no outer 'paper' protective layer, I know their shelf life is extremely limited.
Im guessing its a combo of over watering ( my fault last year , mother natures this year), and poor drainage. Maybe the ground level is firm, or clay like allowing the water to sit once it drained through the first 8 inches or so. And the reason the double raised bed doesn't have the same issue, is because it has an extra 10 inches of height, so even if the water pools, its still a significant distance from the garlic roots.
Im thinking my options are:
1) Amend much deeper too avoid pooling
2) Do a double raised bed ( raised bed on top of this one), to create a distance from the pooling water
3) Just move the garlic over where there is no issue, and plant something that wont easily be affected by water pooling 8 inches below the surface
***Last year ( and this year) after I had the issue with the garlic and dug it up, I replaced it with zucchini , pole beans and cukes, which all did fine in the same location. Garlic was the only one that had an issue here. Doing the same thing this year. I already got my pole beans , cuke seeds and 8 ball zucchini started in cells (weren't supposed to Gert started for another few weeks, since I thought id be harvesting the garlic in July). And hopefully, at least these replacement crops will do as well as last year.***
This is where the Wisconsin and Country fair will go,.
And on a happier note, the little leaf which didnt look to great, seem to be kicking in with this warm humid weather.