If winters are extremely mild or bulbs are right up close to the house
where they stay a bit warm, many crocuses will not bloom because they did
not have a sufficient dormancy period, then if suddenly they get a real
winter chill they do fine that spring.

If bulbs were cheap & tiny, they could have taken a couple years merely to
mature sufficiently to bloom.

If the crocus grass was mowed or cut back every year, that would've kept
the bulbs too weakened to bloom, since they need the grass the entirety of
spring in order to charge up with enough energy to bloom the year after.
So too if slugs ate the grass before the bulbs were recharged, no blooms
the following year.

Snails, slugs, moth larvae, beetle larvae or even mice or a squirrel, may
have eaten the flower buds as they emerged; mice LOVE crocus buds, & the
bulbs too if they're planted too shallow.

Or they did flower but weather patterns (like hard beating rain & zippo
for sunlight) caused them to last only a day or two instead of two to four
weeks, so they were beaten down & bug-eaten before you noticed them. This
happens easily with crocuses which can be spectaculous one year & duds the
next depending on timing of sun & rain patterns.

-paghat the ratgirl
--
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