A botanical spring puzzle

Why are there no native super early flowering plants in our area?By “super early” I mean flowering some five weeks before forsythia. All the ones I know are alien.Most are “bulbiferous” and go dormant in summer. Snowdrops, Galanthus nivalis, and Snowbells, Leucojum vernum, are both in the amaryllis family; crocus species, in the iris family; and scilla, in the asparagus family belong to this category. Others, like cyclamen coum, primrose family; winter-aconite, eranthis hyemalis; and adonis amurensis, buttercup family; grow from tubers, thickened roots.None of them is a native plant. Although all mentioned families exist in the New World as well, none have produced super early flowering species similar to what exists in Eurasia, nor have other plant families.

We wait for our beautiful native spring wildflowers — Virginia bluebells, Dutchman’s breeches, Trilliums, Trout lily, etc.In our garden, the earliest native will be Bloodroot, by mid-April. By then, a large cohort of alien plants are already in full flower for several weeks, in some cases for over a month.

Why is this roughly four to five week temporal niche in the annual cycle unoccupied? It’s a niche of very low productivity for sure, but nature, famously, abhors any vacuum. Could it be that the physical habitat niche is too small here? What I found, doing some research, suggests it is possible — larger areas are correlated with more speciation according to p. 1149 in Science from March 15, 2025. Eurasia, broadly oriented from west to east, has a very long, uninterrupted temperate and mountainous zone, stretching from Spain to western China. With its many grassland habitats, it provides a huge playing field for evolution. America, by comparison, geographically laid out north to south, contains much less continuous temperate environments suited for crocus.

Until now. Our small, short-cropped lawn at winter’s end mimics aspects of Eurasian alpine meadows. There, before any green grass is visible, crocuses break through the edges of the melting snow cover on the late winter lawn. Species crocuses have conquered that new habitat, first in European gardens, and now here too. Before the grass grows too tall, they benefit from abundant sunshine to nourish their bulbs for next year. That’s another reason to delay mowing as long as possible. A lawn may not be a natural habitat, but if free of herbicides, pesticides and fertilizers, it is after all just another meadow.

Perhaps another reason for missing March flowers is a lack of early pollinators.On one of these rare sunny, warm days in early March, I wrote in my diary: “03/09/23 - many honeybees on winter aconite, also a fly …”and some honeybees on crocus as well. Like winter-aconite and crocus, honeybees are not native in America and I have never seen them again that early, ever since a nearby beekeeper gave up.Looking at the amounts of pollen in these crocus flowers, they must be an abundant food source for all kinds of bees and bumblebees. However, only honeybees — whose colonies survive the winter in hives — can quickly deploy a large number of pollen collectors. Flowers and insects co-evolved a myriad of interdependencies, so super early flowering plants, cold adapted, depend on enough pollinating insects to make flowering through the snow worthwhile. On high alpine meadows there may be other early up-and-about insect species, but here it is honeybees which profit most.

Snowdrops, snowbells, crocuses — they don’t compete with any natives, but fill a manmade, unoccupied niche.The very earliest to flower through the snow, adonis amurensis and cyclamen coum, grow in light shade and slowly form stay-in-place clumps. Unless in a controllable setting, I would stay away from squill — Scilla siberica — which is a very aggressive naturalizer and easily escapes.

As we wait for our many native beautiful spring flowers, how nice to have these aliens, such benign aliens for a change, to cheer up a March-brown lawn.

Fritz Mueller lives in Sharon.