So, this is a question I ask myself every year:
Is this variety of garlic ready to be dug?
I ask myself this roughly one-hundred times in the last weeks of July, and all the way into August, as I have quite a few varieties. After twelve years of growing garlic to sell, I still get nervous about when to dig.
It's a ticklish thing, you want the bulb to be nice and mature, but you want it to also have keeping quality and nice layers of wrappers so that it is salable and pretty.
The fail-safe way is to count the leaves, I think. Most bulbs will have six to eight leaves, and if about three of the bottom leaves are drying down, you can be sure it's not just a drought causing that - it's ready!
40-50% of those bottom leaves, dry or yellow, that's the clue.
If you look at the whole plant, it should be more green than yellow, because the dry leaves get smaller in appearance.
Sometimes within the row there will be some variation of when the plants are ready, even if it's the same variety, (In my case, out in the field with 400 foot long row, that variance can sometimes be caused by tile drainage, as in, where the soil was nice and the garlic did better, and so is larger, greener and later) but the variance should be pretty minimal. If a few odd plants are yellow, and the rest looks green, well, that could be diseased plants that are suffering, so don't go digging up the whole row thinking they must be ready, in that case.
Always be gentle with the bulbs. They bruise if handled roughly. It may not show up right away, but cloves that are damaged might mold or dry up later.
For Pictures and a more detailed explanation of how and when to dig, as well as some calendar dates to shoot for, see the blog archive 2015 "Harvesting Garlic" July 11.
You can usually tell early on how big the harvested bulb will be, based on how thick, or big around the neck of the plant is. Although, a few varieties have odd bulb - to - plant size ratios and can have really thick necks, with puny bulbs, or vice versa. Purple Stripes come to mind, they can have large plants with smallish bulbs. Turbans on the other hand can have respectively large bulbs compared to how thin and tiny the plant looks.)
Turbans seem to keep better if they are harvested early - as in, when only one to two leaves are dry.
In some kinds of soils the wrappers of Turbans and Asiatics will also split if left in the ground as long as other garlic, so be mindful of that.
And where you put them to dry does have some importance as well. Keep them out of direct sun - that can cause the cloves - which are actually "storage leaves", to turn green, same as an onion or potato might,( they are blanched by being under ground while growing, so they are white/cream coloured and need to stay that way). Indirect or artificial lighting is fine. Direct sunlight can also "cook" them, and excessively high temperatures can also cause the cloves to deteriorate (Something called Waxy Breakdown) so try to avoid places that lock hot air into the drying area when you are choosing a spot for drying your garlic. A box fan or oscillating fan and an intake/out take are all that's needed to keep air moving in the drying shed.
I always recommend the slow way of drying garlic - with the whole stalk attached until it is cured and dry. Any home gardener can do this method, it's easy to make bundles of 8 -10 bulbs and hang them somewhere, or lay them out on racks or in open baskets. It takes about two and a half to three weeks, depending on the size of the garlic and how dry the air is, and you have a better product from it.
The flavour of fresh dug garlic is hot, juicy and simple, so it is best to wait until the whole plant is dried down anyway. Garlic tastes the best about two months after it's dug - it reaches a maturity of flavour that brings out depth and character, and then it begins to very slowly decline into the winter months, eventually tasting simple and firey again, but dry, instead of juicy.
Well, I must go out and check on a few of the early varieties again, even a day or two can make a difference in how they look. I've dug a few Turbans already, but nothing else, so I'm wondering if the harvest will be a bit late this year.
All the best with your harvest! I hope it's a good one! Julie