2024 is shaping up to be a really good year for autumn colours. Triggered by the recent cold nights, the emblematic sweet gums of Burbage Road, Half Moon Lane and many of our smaller streets are clothed in stunning purple, red, burgundy, orange and yellow leaves. Most of the cherries are already past their best, including the Yoshino cherries of Winterbrook Road, which reliably put on an autumn display almost as breathtaking as their famous spring blossom. Now it's the turn of the ginkgos and tulip trees, in their bright yellow autumnwear.
Other street trees make their seasonal mark in a different way: with bright and cheerful berries in late summer and early autumn. Except that they don't. In fact, there isn't a single street tree in Herne Hill that bears true berries. You probably haven't even got berries in your fridge, even if you've stocked up well at Sainsbury's or Tesco. Let us explain. (If you want to skip the botany bit you can scroll down now to the pretty pictures of red non-berry fruit).
First, some elementary science
Most of what we call ‘berries’ are nothing of the sort. We generally take the word to mean any small edible fruit, and that's exactly what the Anglo-Saxons had in mind when they were using the Old English term 'beri' 600 years before the Norman conquest. But the development of modern botany in the 18th and 19th centuries gave a different perspective.
That was the era of giants like Carl Linnaeus (the Swedish biologist who was the first to systematically classify plants and animals), Alexander von Humboldt (the German naturalist, explorer and ardent plant collector) and Charles Darwin (the English polymath who fathered evolutionary biology). Nowadays botanists know the structure of every plant in microscopic detail, its place in the global taxonomy and the Latin name for the tiniest fragment of its flower. And now we can answer the questions you're bound to ask.
So what precisely is a berry then?
It's a fleshy fruit.
It has two or more seeds.
It's indehiscent, meaning the fruit doesn't split or burst open to release its seeds like the pods of beans, peas and gorse do. Instead the flesh decomposes or birds and animals distribute the seeds.
Finally, it develops from a single flower that has a single ovary. The ovary is the part of the flower that contains the ovules, which develop into seeds once they're fertilised. The ovary itself becomes the fruit.
Can you name some berries?
Certainly. Here we go:
Tomatoes
Bananas
Red, yellow, orange and green peppers
Aubergines (eggplants)
Kiwi fruit
Grapes
Really? Are you serious? What about strawberries, blackberries and raspberries?
Sorry, no. They're actually 'aggregate fruits', made up of many smaller fruits formed from multiple ovaries.
Are there any 'berries' in the shops that are real berries?
Yes, you're in luck: blueberries and cranberries are the real deal.
Have you got any more fruity surprises for us?
Just a couple:
Citrus fruits are a specialised kind of berry called a 'hesperidium'.
And melons, cucumbers, squash and pumpkin are another type of berry known as a 'pepo'.
Where does all this leave our fruiting street trees?
Well, our apples, pears and quince are 'pomes', an entirely different group of fruits from the berries.
In pomes, the fleshy part of the fruit doesn't develop from the ovary but from other parts of the flower, and the seeds are encased in a tough core.
Our whitebeams and hawthorns, two of the October fruits we'll be looking at more closely in this blog, are all pomes.
The cherries, plums and the walnut in the Delawyk estate are all stone fruit, more properly known as 'drupes'. They have a single hard pit, or stone, in the middle that contains one or more seeds.
The holly, another of our October fruits, is also a drupe, though it contains three to six little stones, not one big one. It's toxic to humans and pets (although leaves from the top branches - the ones that aren't prickly - used to be fed to sheep and cattle).
And last but not least, the bright red (and equally poisonous) 'berries' that hang in Delawyk's yew trees aren't even fruit, let alone berries. Conifers like the yew don't have flowers or fruit, but they do carry seed-bearing cones. The yew 'berry' is in fact a female cone, known as an 'aril', that forms a cup around the seed.
Common hawthorn (Crataegus monogyna)
Let's kick off our review of the best fruiting trees for late August with the common hawthorn, a key element of the traditional British countryside. It's found in hedgerows everywhere and on scrubland, where it's an early coloniser. Armed with short thorns, it helps keep livestock from straying and provides protection for nesting birds that value its dense network of twigs. It's the May tree of song, poetry and legend and of mayflowers and haws, the customary name for its dark red fruit.
The hardy and resilient common hawthorn is native to Britain and has enormous wildlife value. Its sweet-smelling blossom feeds pollinators and dormice, its leaves feed moth caterpillars and its long-lasting pomes (not berries!) feed thrushes, starlings, finches, blackbirds, redwings and fieldfares as well as migrating birds. The 8-10 mm long fruits each have a core containing a single seed inside , which explains the 'mono' in the hawthorn's Latin name. After enjoying the flesh of the fruit the birds usefully disperse the seeds in their droppings.
In the language of flowers - something well-bred Victorians would employ to send coded messages to secret lovers - hawthorn symbolises 'hope', perhaps because its appearance in May meant winter was over and summer was on its way. In this time of climate change the May tree's vernacular name is a bit misleading. We first spotted its flowers in mid-April this year, a good two weeks earlier than in the past.
The Woodland Trust has a nice 'Year in the Life' time-lapse video showing the hawthorn through the seasons and another showing its leaf and flower buds bursting open. Locally you can see common hawthorns along the steep section of Greendale; in Sunray Gardens; on Red Post Hill outside the Cassinghurst flats; and at 94 Burbage Road, where there's a tall upright tree, probably a fastigiate Crataegus monogyna 'Stricta' .
Midland hawthorn Crataegus laevigata)
The second of our native hawthorns. the tough and tolerant Midland thorn is less widespread in the wild than the common hawthorn, being mostly confined to shady woodlands on the clay soils of south and central England. But it's much more frequent in parks and on town streets in the form of the 'Paul's Scarlet' cultivar, with its dense clusters of dark pink double flowers in the spring ('double' signifying layers of extra petals). Unlike its single-seeded cousin, the Midland thorn has two to three seeds inside each small red haw, or pome. And according to the Woodland Trust, the fruit can be used to make jellies, chutneys and wine.
'Paul's Scarlet' was first discovered in 1858 in a garden in Waltham Cross, Hertfordshire, as a 'sport' from another pink-flowered Midland thorn. 'Sports' are random shoots that appear quite distinct from the rest of the tree. William Paul, a well-known nurseryman in Waltham Cross, was the first to propagate a new tree from this sport and attached his name to it.
Herne Hill has three 'Paul's Scarlets' that we know of: one vigorous tree at 122 Casino Avenue; a healthy young one at the top of Hollingbourne Road, planted in March 2023; and a rather scraggy specimen at the bottom of Ruskin Walk where it joins Half Moon Lane. Further up Ruskin, on the same side of the road, there's a very fine example in the front garden of no. 66.
Native hawthorn leaf shapes
Hawthorns can be difficult to distinguish from each other because they naturally hybridise very easily. So their leaves can vary a lot from what you might see in field guides. But as a rule the common hawthorn's leaves are pale green with 3-5 deeply cut lobes from the tip to the stalk. By contrast, the dark green, shiny foliage of the Midland thorn is only lobed at the pointed end. The leaves of both species grow up to 6 cm long.
Broad-leaved cockspur thorn (Crataegus x prunifolia)
We're leaving the native hawthorns behind now and looking at three distinctive hybrids. The first is one of our long-time favourites, the broad-leaved cockspur thorn. We love it for its constant interest and beauty: dazzling white flowers in springtime; dark glossy leaves in summer; bountiful fruit in autumn on a background of yellow, dark brown and crimson foliage; slender thorns on the exposed branches in winter; and a graceful silhouette at any time of year.
The fat, 15 mm long fruit are crowned with five-pointed black sepals that once protected the flower bud and now make them look like baby plum tomatoes.
The English name gives away one half of its probable parentage, the Crataegus crus-galli or cockspur thorn from North America, its branches bristling with vicious thorns that can reach 15 cm long. The other side of the family tree is unclear but as the International Dendrology Society says on its website: "Whatever its origin, C. prunifolia is one of the most admirable of all thorns."
Like all hawthorns, the prunifolia is compact and drought-resistant, which makes it a good choice for the hot, dry years ahead. We recommended the tree to the council and six saplings were planted here in 2022/23:
two at the Half Moon Lane end of Carver Road, one on each side
one at the top end of Hollingbourne Road, alongside the nursery school garden
one on the grassy crescent outside 65 Red Post Hill
one at 52 Ruskin Walk
and one at 4-6 Warmington Road.
All are doing well. They join our senior prunifolia outside 35/37 Half Moon Lane and a low-growing tree in the top cul-de-sac on Casino Avenue, in front of house no. 7.
Hybrid cockspur thorn (Crataegus x lavallei)
We only have one example of this next hybrid hawthorn, at 19 Hollingbourne Road, but it's definitely worth planting more. It's another descendant of the cockspur thorn, this time a cross with Crataegus mexicana, the Mexican hawthorn. The big, orange, edible fruits of the Mexican tree are mirrored in the striking orange pomes of the hybrid. They remain right through winter, unlike its cousin, the broad-leaved cockspur thorn, which drops its own fruit at the end of autumn.
In fact the whole life cycle of the hybrid cockspur thorn runs slower than the other hawthorns. It flowers in late spring and holds its dark green, narrow, glossy leaves until December, although they don't show much in the way of autumn colour apart from a reddish tinge. The upright, spreading habit is also unusually neat for a member of the hawthorn family.
The name Lavellei refers to Pierre Alphonse Martin Lavallée, a French botanist who set up an arboretum south of Paris where the hybrid cockspur thorn was first observed around 1880.
Grignon’s thorn (Crataegus x grignonensis)
Our final hawthorn is the rare and strange Grignon’s thorn, which surpasses the hybrid cockspur thorn by holding on to its bright red fruit until after the pretty white blossom has appeared in April/May the following year. Like the Lavallei it was first noticed in a collection in northern France, the Arboretum de Grignon, around 150 years ago and it too may have the Mexican hawthorn as a parent.
Their leaves are unique for hawthorns, more sharply toothed than deeply lobed, but as you can see in the picture on the right they vary even on the same tree.
There are three of these very uncommon trees on Ruskin Walk, at nos. 29-31, 40 and 79, but they're getting on in years and their current crop isn't as abundant as in previous seasons. We'll have to keep an eye on them.
Whitebeam (Sorbus aria)
Here's another native tree that deserves to be more widely planted in Herne Hill. The whitebeam has a fine upswept profile and striking green leaves that are silvery-white on the underside. Before they fully unfurl in spring the leaves stand in tight upright bunches, showing only the conspicuous reverse, giving the whole domed crown a frosted appearance. Pretty heads of white flowers, loved by bees, follow and in September a modest harvest of fruit (pomes) that start green then ripen to red and orange. They don't last long once the birds spot them, but the pale yellow and brown autumn leaves remain for a while.
As well as its ornamental value the tree is certainly tolerant of urban conditions - as you can tell from the three whitebeams planted outside the Milkwood Road entrance to Tesco and a further three directly opposite by the station subway entrance. The Milkwood trees have been frequently bashed by vehicles but are still thriving, even if some of them are leaning at a perilous angle.
We only have three whitebeams on the streets of Herne Hill: at 80 Holmdene Avenue, 66 Ruskin Walk and 17 Nairne Grove. In the wild they're mainly found, in limited numbers, on chalk and limestone soils in southern England, but there are eight extremely rare species that live only in the Avon Gorge. One is the Bristol whitebeam (Sorbus bristoliensis) and another the Avon whitebeam (Sorbus avonensis) - both classified as endangered.
Swedish whitebeam (Sorbus intermedia)
October is too late for the fruit of most rowans (Sorbus aucuparia), but a newly planted Swedish whitebeam at 17 Burbage Road gave us an inspiring display for such a small tree. It's a clone called ‘Brouwers’ and features branches that have a more ascending habit than a regular Swedish whitebeam. You can see another small Swedish whitebeam on Burbage Road near the junction with Half Moon Lane, where it's unfortunately overshadowed by the huge lime trees that stretch down to the doctor's surgery. And there's a bigger one on Casino Avenue, at the side of 54 Sunray Avenue.
Apart from the whitebeam, the Swedish whitebeam and the rowan there's a fourth species of Sorbus in Herne Hill: the bastard service tree (Sorbus x thuringiaca), a hybrid between the whitebeam and the rowan. We covered them all in more detail in our Spring 2024 blog, including this montage of the different leaves. (Clockwise from top left the leaf images show whitebeam, Swedish whitebeam, rowan and bastard service tree),
Wild service tree (Sorbus torminalis)
Excitingly for fans of unusual street trees there’s a fifth Sorbus on its way: another native, but rare in the countryside and in the city, it’s the wild service tree. It’s on this season’s planting list for a spot outside 45 Casino, on the grass strip between the privet hedges of the houses and the hornbeam hedge at the roadside.
Wild service trees are a good indicator of ancient woodland, but they’re hard to find. If you look carefully, though, you can see a few in a very modern woodland, Village Copse in Dulwich Park, planted in 2006 next to the cricket nets. Their unusually shaped leaves are dark green and glossy in comparison to other Sorbus. And their green-brown fruits, known as 'chequers', were once used to flavour beer. That could be why so many pubs are called The Chequers.
Common holly (Ilex aquifolia)
We're now moving away from fruiting trees of the rose family (Rosaceae) to the 300-member holly family (Aquifoliaceae). We've got just one species in SE24: the charming common holly, a British native except in the very far north of the Scotland mainland, Orkney and Shetland. In terms of fruit, these gleaming little stars of a thousand Christmas cards are drupes. And those blackberries growing among the hollies in the planting bed between 81 and 95 Red Post Hill are not berries either: they're aggregate fruits.
Which takes us back to where we started.
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