Even when you choose a medium sized clove to plant, it should be from your best and biggest bulbs. Otherwise there is a risk of growing smaller bulbs. If you plant from small bulbs, you'll get small bulbs, and I guess if you repeat that over time they would get smaller and smaller.
Since I started growing (only six years I think) we have had some cool cloudy not sunny seasons when my garlic didn't size up as big as in a sunny year. But that doesn't stop them from doing better the following year if conditions are better. Another reason for smaller bulbs is if they aren't in a fully sunny spot. I learned that the hard way, because I'm surrounded by trees and not enough fully sunny places. And another possible reason for smaller bulbs is of course, inadequate ferts and soil conditions. Or diseases like the rust which weakens the plant.
Depending on your location I suppose the garlic could get smaller and smaller as you described, if the garlic never really gets what it wants in terms of sunshine, soil conditions, freedom from disease.
|