For a few weeks they release pollen into blustery March breezes, then fall the leaf canopy unfolds. Enjoy them while you can with our guide on how to identify catkins:
Hazel - Corylus avellana
Golden catkins on bare twigs release clouds of yellow pollen that seem to dissolve in the air, destined for tiny female flowers that are just clusters of carmine stigmas protruding from a bud.
Alder - Alnus glutinosa
Longer, more knobbly and darker than hazel, these are the first catkins to shed pollen in spring. They’re carried on the tips of twigs, often alongside clusters of tiny red-tipped female flowers.
Goat willow - Salix caprea
This has separate male and female trees. Male catkins are clad in golden stamens; female catkins are spiky and green. Both secrete nectar – key energy for bees and butterflies in early spring.
Silver birch - Betula pendula
Male catkins elongate and shed pollen at the same time as leaf buds open. Female catkins are short and point upwards, hanging downwards after pollination, when the seeds develop.
White poplar - Populus alba
These long, fat, red-tinged catkins are often carried at the top of the tree, so you may need binoculars to appreciate them. Easily dislodged by wind, they litter the ground after a gale.
Walnut - Juglans regia
The short, fat, green catkins shed pollen at the same time as the leaf buds release their grip on the purple-hued foliage. Female flowers are shaped like little pots, tipped with a pair of curved stigmas.
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