Unexpected treats
Uncommon to their genus, these beauties light up autumn
Hamamelis virginiana
Bears yellow, scented flowers in mid to late autumn, rather than winter.
Gentiana sinoornata
Acid-loving, evergreen perennial that produces brilliant blue trumpets late in the year, not in spring.
Galanthus reginae-olgae
This autumn-flowering snowdrop species blooms from September onwards!
Cracking colour
Leaves start to produce their autumn colours when the days shorten and photosynthesis ceases for the season. When chlorophyll production stops, the pigment that remains gradually breaks down to reveal the yellow and orange xanthophyll pigments that were masked by the green. The sugars that remain in the leaf, meanwhile, convert to red and purple anthocyanins – a process promoted by bright light and cool temperatures, which often herald glorious woodland displays. Either on or off the tree, these red, orange and yellow pigments also gradually break down, and the leaves become tannin-brown.
Winter sleep
Many plants become dormant to be able to survive the adverse conditions of winter. Low temperatures and light levels make it difficult for plants to grow, so they shut down and conserve their resources for when things improve and they can grow quickly. Leaves fall off due to a process called abscission, where a corky layer gradually forms between the leaf and the stem. This separates it from the rest of the plant so it dies.
Evolutionary advantage
Berries become brightly coloured as they ripen and the anthocyanins and other pigments develop. Interestingly, on an evolutionary basis, this seems to work two ways. The colour changes allow the plants to signal to birds and animals that the fruit’s ripe and ready, so that it gets eaten and the seed gets dispersed. Equally, our eyes (and those of other animals) have evolved effectively to be able to spot essential resources like food and mates. Being able to see the colours of ripe fruit improves our chances of survival and it’s hypothesised that an ability to see red, orange and yellow well is part of this.