Picture: Ashridge estate. Click here for more April tree photos.
One of the most dramatic changes in the countryside in April is the return of foliage on bushes and trees, turning the landscape from drab brown to glorious fresh greenery. On the way, various trees get briefly highlighted and woods acquire a lurid bright green appearance that is quite overpowering on sunny days.
As explained in March trees and shrubs, this process has already started to some degree in that month. By the end of March hedgerows and the understorey - the lower level of woods - is dotted with green patches, or may already be showing a widespread "green fuzz" of new growth.
The understorey growth includes various shrubs and small trees, as well as saplings of larger tree species that put out leaves early, all presumably programmed to do so by evolution in order to catch the light reaching the woodland floor before the tree canopy closes.
Among larger trees, weeeping willows leaf right from the start of March while hornbeams and horse chestnuts are starting to do so at the end of the month.
In the first half of April various other species join in, before a sudden explosion of greenery takes place round the middle of the month. Usually coinciding with the leafing of oaks, this leaves the woodland looking mainly green apart from a few standouts such as beech, ash and sweet chestnut.
The timing of all this can vary, of course. In 2011, 2020, 2024 and 2026 the big explosion of greenery happened as early as the second week, while in 2013 and 2015 it was not till the fourth week, and after the cold April of 2012 it did not happen until the first week of May. In 2021 leafing proceeded more or less as normal in the first half of April, but continued cold weather then put it into slow motion and the treescape was not widely green until the second week of May. In 2018 a cold start to the month and then hot weather mid month meant everything happened in a rush in the third week.
The first leaves on shrubs
The very first new leaves appear way back in winter. As well as evergreens such as holly and yew, some deciduous plants never entirely lose their foliage - for example privet and buddleia - or start putting out new growth as early as December or January - for example honeysuckle. The new shoots on buddleia grow to about two thirds of their final size during March and then finish the job in the first half of April. Honeysuckle foliage is usually complete by the first or second week of April.
Garden privet, the familiar garden hedge plant, which has more rounded leaves, also adds new foliage in March, a process that is usually still finishing in the first half of April. Wild privet, which has narrower leaves and grows in woods and hedgerows, as well as on downland, can be at an earlier stage, and some (particularly on downland for some reason) can even be entirely bare at the start of the month. Most are still not in full leaf until the second half.
Bramble for the most part also keeps a few leaves over the winter (at least in shadier spots: out in open fields it goes almost entirely bare) and as early as mid March puts out new leaf shoots from the middle of its stems. These new leaf shoots can be quite tentative in the first half of April and they often don't reach full size until the second half. Being so widespread, they contribute a lot to the greening of the landscape.
A much less common plant that can be mistaken for bramble is raspberry, which has similar foliage but stems that grow upright (rather than horizontally as with bramble) and which are only slightly prickly. Its leaves emerge pretty much on the same timetable as bramble - ie first shoots from mid March onwards, with leaves reaching full size by mid April. In the second half of the month it may even put out flower buds.
Another big contributor to the greening of hedgerows and woodland understoreys, is hawthorn, which is often full out, or nearly so, right at the start of April, covering large areas with a glorious tide of green. Some of the leaves - particularly on smaller or younger bushes - can appear as early as the start of March, but the main wave of foliage - that is, most bushes bursting into leaf - is usually not till the end of that month (the third week of March in warmer years, as late as the second week of April in colder ones). The leaves remain small for a week or two.
Other less noticed contributors to the greening of hedgerows and the woodland understorey include cherry plum, which leafs once its blossom is over, typically some time in late March, and elder, whose leaves have also been growing slowly since as early as January (and particularly in March) and rapidly grow to full size in the first half of April.
Snowberry - a park or garden shrub, but sometimes found in the wild - starts to put out foliage from the second week in March and usually looks in full leaf in the first or second week of April, though its leaves continue to grow and do not reach their full size for another couple of weeks.
Dog rose also starts to tentatively put forth leaves in March, but its foliage does not usually reach its full size until the second half of April. Dogwood leaves can remain small till the fourth week, but stand out attractively against their maroon twigs.
In hedgerows on chalk soils the climbing plant traveller's joy can have a few tentative leaves in the second half of March, but they have not progressed much by the start of April and the plant is usually not fully leafing till the third or fourth week of the month.
On blackthorn the falling blossom (which can be any time from the first week of April to the first week of May - see April blossom and shrubs) gives way to new foliage, though there can be a short gap between the two in which the bush looks a dispiriting brown mess - though there are tiny green shoots if you look closely. Some smaller blackthorns go straight to leaf without flowering at all, or have lower twigs leafing while the upper ones are still in flower.
The tree sequence
Moving on to trees, the very first to leaf is, perhaps surprisingly, weeping willow, which can put out new leaves and catkins as early as the first week in March, and which shines a bright yellowy green in the landscape. This effect usually lasts a little way into April before it fades to a more normal green. (In 2018, exceptionally, weeping willow did not leaf until the second week of April and never quite attained its normal brightness.). The catkins (which nearly always seem to be yellow male ones) fall shortly afterwards.
Hazel, another important hedgerow and woodland understorey plant, tends to have small new leaves at the beginning of April, having started in mid to late March. They remain very small until the second half of April, however. At this early stage they look almost identical to those of hornbeam, to which they are related. Only towards the end of the month do they start to take on their final, more rounded shape, and even then they may not attain their full size until some way into May.
Hornbeam leaves are usually preceded by a mass of male catkins. Typically this happens in the second half of March, though occasionally there are years when there are very few (eg 2025) or none (2020). Leaves then start to appear about ten days later - usually the first or second week of April, making hornbeam the first source of greenery in the upper levels of woods. Once the leaves are out, the catkins last another week or so before falling to the ground.
While the catkins are still on the tree, one is aware of just how many hornbeams there are in some parts of the south east, for example the Weald: they are not common elsewhere in the country, but in our region there are whole woods of them. Along with the leaves, the almost invisible female flowers appear, drooping at the end of the twig, and towards the end of the month these morph into thin tassels, the beginnings of the tree's seed clusters.
Another large tree that leafs early is horse chestnut, whose brown sticky buds expand into monstrous ovals that look like some weird alien fruit, and then overnight produce limp bright green leaves. Typically this process starts at the very end of March but does not get far, with the leaves mainly emerging in the first or second week of April, and taking as much as two weeks to grow to their final (enormous) size.
Once the leaves are fully grown, the flower spikes start to appear on horse chestnuts. Squirrels eat the flower buds and discard the leaves around them, which is why you sometimes find fresh leaves on the ground. In 2017, 2020, 2024, 2025 and 2026 the flowers themselves came out from the third week of the month: otherwise, they appear at the month's end or in early May.
At the start of April, or increasingly in recent years in the last week of March, Norway maple seems to be bursting into bright yellow-green leaves. But on closer inspection these are flowers, with some leaflets. The tree remains a striking sight for a couple of weeks. Once the flowers go over (leaving a yellow carpet on the ground), they turn into tiny winged seeds and the leaves grow to full size.
Larch can be briefly quite noticeable in early April too. The only coniferous tree to lose its needles in winter, it has already started to put out soft tassels of new greenery in the second half of March. These are often quite small at the start of the month, but explode into a mass of bright greenery in the second week.
Notice also the cone-like pink blooms on larch: these are the female flowers, a floral version of the seed cones they will eventually become. These have also started in March and get gradually bigger as April goes on. The male flowers (seen on the same tree) are yellowish and small, looking like undeveloped buds.
Also at the start of April pussy willows (a common name taking in goat willow or sallow and grey willow) are at the height of their catkin phase. There are two types of tree. Males mostly lose their yellow catkins either at the end for March or in the first week of April; leaves then appear, though they remain fairly small all month. Meanwhile female trees have green catkins and small leaf shoots all month. Towards the end of the month the catkins might start producing their fluffy seed.
Another willow - osier, which grows by rivers - has similar male catkins to pussy willows, though more neatly arranged and densely packed on the branches. Once its catkins fall, it puts out clusters of long thin leaves. Like pussy willows, its female trees retain their catkins till early May, when they seed and fall.
Much more common than osier in the south east is crack willow, which also often grows by rivers. It puts out catkins and small leaf shoots as early as the start of the month, the male catkins yellow and sometimes looking like curly caterpillars, the female green. The male ones often fall to the ground later in the month, but may last some way into May; the female ones remain on the tree. The leaves remain small all month.
The very similar white willow has less glossy and slightly darker leaves than crack willow, with a slightly hairy underside, and its new twigs are brown while those of crack willow are yellowish (though the two species do also interbreed). It slowly puts out leaves and catkins during April, both male and female ones looking green at this stage and so being hard to tell apart, the texture of the female ones a bit more like a cluster of seeds. Later in the month the male catkins may start to turn yellow. As with crack willow, the leaves remain quite small even at the end of April.
In the first or second week of April (or even at the very end of March: it seems to be quite variable from tree to tree) the short brown catkins that have hung on birch trees all winter lengthen out, causing big problems to hayfever sufferers (birch pollen is very allergenic). The leaves generally appear at the same time, though on some trees they are a bit later: they then grow at varying rates, with some trees greening up quite quickly. The catkins last until late in the month or sometimes into May, but in truth it is quite hard to spot when they finally fall off because there are more interesting things to look at.
One is sycamores. A few saplings and smaller trees that are not going to flower may have started leafing in late March, but at the start of April most mature trees are still just showing large green buds. They can be surprisingly slow about bursting into leaf and the timing of this can vary greatly from tree to tree - anytime from the start to the end of the month, basically, with nearly bare trees not uncommon even at the month's end.
Once they do decide to stir themselves, sycamores put forward very alien-looking shoots (they rival in weirdness the ones on horse chestnut), which resolve themselves into tassels of flowers that hang down like bunches of grapes, and leaves that sometimes look brown and autumnal when they unfold. They may then grow to full size only slowly.
Field maple (our only native maple species) also produces flowers and leaf shoots simultaneously, the flowers initially being more prominent. This happens usually in the second or third week. The leaves are initially small and hang limply, as if drying out, but may grow bigger more quickly on saplings and hedgerow plants that are not going to flower.
Poplars - both hybrid black and lombardy types - have already produced their fat maroon-coloured catkins in March. After the catkins fall, there is a bit of a pause and then in the second or third week of April (the first week in 2026) the leaves appear - olive-coloured or even red-brown initially on hybrid black poplars, where they slowly turn green as the month progresses; sometimes slightly olive on lombardy, but very quickly turning green. Western balsam poplars - traditionally used as windbreak trees in orchards or hop gardens - have had foliage since March and may still have green (female?) catkins.
London plane, more of a street tree than a rural one, puts out new globular flowers in the second week (from the start of the month in central London, and more widely in 2024), the larger female ones hanging down from the tip of the twig, and being sometimes quite red but otherwise a sort of rusty brown or olive green; the male ones small, green or yellowy-green, and a bit further back on the twig. Towards the end of the month the male ones turn fluffy and fall, while the female ones get a little bit larger.
London plane leaves appear at the same time as the flowers, but generally remain small until May (the tree looks a mess while they are in this state). You can also see quite a few of last year's brown seed balls still on the twigs, which may fall and break apart producing piles of silky tassels on the ground, though the timing for this is very variable.
Other trees leafing mid month include alder, lime and rowan, the latter easy to mistake for ash due to its similar foliage. On alders and limes these leaves can remain very small till well into May. The lime ones look a bit like teardrops when new.
Elms are still in flower at the start of the month, and by mid month have bunches of their flat seeds. The ones you see are overhelmingly likely to be wych elm, which is in fact our native species, as English elm is generally only a hedgerow shrub these days due to Dutch Elm Disease. The seeds seem to remain on the branches for a good while before the leaves start to come through at the end of the month, remaining rather small until the seeds fall in May. Once developed, a sharper point to the leaves distinguishes wych elm from English elm.
One of the stranger tree sights of April are the pale leaves of common whitebeam, which unfold from an upright centre like tulip petals from the second or third week, and are very prominent in the landscape by virtue of their greyish (or silvery?) tinge. They can remain fairly small all month, however, still in their tulip-like clusters even at the month's end. Greyish flower buds appear but (apart from in 2026...) don't bloom until May.
The kings of the woodland
You might say that all of the preceding shrubs and trees are the warm-up acts for the big event, which is when oaks come into leaf. They are such a dominant tree that they turn whole swathes of the countryside from brown to green. You could claim, indeed, that this is the moment when winter is finally banished from the landscape.
Oaks produce leaves and yellow-green tassel flowers simultaneously, but the leaves are slow to grow and the flowers dominate to begin with. You have to look closely to see this, however, as from a distance the flowers look like new foliage. On trees with no or fewer flower tassels, the leaves grow more rapidly.
All of this usually happens either in the second or third week. This at least is when the big wave occurs, but oaks are particularly sensitive to temperature, leafing eight days on average earlier for each degree rise, while ashes only leaf four days earlier, and - as is perhaps not surprising, given their long lives - they seem to have their own particular responses to the micro-climates they live in. It is therefore not unusual to find one leafing a bit earlier, or only just starting at the end of the month (which is when all oaks started in cold 2013).
Another very striking tree contribution to the treescape is from beech. While some leaves may be seen from the second or third week of the month, the main wave of new foliage is typically not till the fourth week, or even the first week of May in colder years. Some large trees further north (eg on the Ashridge estate near Tring) or high up (eg on top of Leith Hill in Surrey) may come out quite a bit later than the main mass. Leafing is accompanied by the appearance of male flowers, though this is very variable - lots some years, almost none in others.
When new, beech leaves seem incredibly bright and hang in limp lines like washing hanging out to dry, making them one of the more breathtaking sights in the woods, particularly when backlit by the sun. Their appearance often coincides with the fullest phase of the bluebell season, the luminous green leaves providing a brilliant backdrop to the purple-blue of the flowers.
Beech hedges also make an amazing switch. They keep last year's brown leaves all the winter but at some point in April dump them and put out bright green new ones. Unless you have one in a street near you, it is quite hard to catch them in the act: they just seem to change overnight.
By this point most of the bare trees you see are ash. It puts out its strange flowers - looking like frizzy lettuce - in late March, meaning they are at their best at the start of April. There are in fact two types - the more compact male ones and the female ones which are already flecked with the seeds to come, though it is only as the latter grow larger that the difference becomes obvious.
Birds such as wood pigeons and blue tits enthusiastically peck away at both types of flower. Within a week or two the male flowers fall to the ground while the female ones lengthen into feathery fans and slowly become more seed-like.
From a distance these seed fans can make ashes look as if they are leafing, but mostly they do not actually do so until the very end of April, the first week of May, or - in 2012, 2014, 2016, 2019 and 2021 - the second week. Even in normal years their foliage can remain tentative until late in May.
Exceptions to this were 2020 and 2026, when leafing started quite widely from mid April and leaves were mid-sized at the end of the month. Also 2024, when female flowers were scarce and many female trees put out small leaves from mid April, though they did not grow very large by the month's end.
One other laggard is sweet chestnut, which mostly does not leaf till May, though towards the end of April you may see some small leaves, particularly on saplings or trees that have been coppiced in the not too distant past.
More April pages:
© Peter Conway 2006-2026 • All Rights Reserved
One of the most dramatic changes in the countryside in April is the return of foliage on bushes and trees, turning the landscape from drab brown to glorious fresh greenery. On the way, various trees get briefly highlighted and woods acquire a lurid bright green appearance that is quite overpowering on sunny days.
As explained in March trees and shrubs, this process has already started to some degree in that month. By the end of March hedgerows and the understorey - the lower level of woods - is dotted with green patches, or may already be showing a widespread "green fuzz" of new growth.
The understorey growth includes various shrubs and small trees, as well as saplings of larger tree species that put out leaves early, all presumably programmed to do so by evolution in order to catch the light reaching the woodland floor before the tree canopy closes.
Among larger trees, weeeping willows leaf right from the start of March while hornbeams and horse chestnuts are starting to do so at the end of the month.
In the first half of April various other species join in, before a sudden explosion of greenery takes place round the middle of the month. Usually coinciding with the leafing of oaks, this leaves the woodland looking mainly green apart from a few standouts such as beech, ash and sweet chestnut.
The timing of all this can vary, of course. In 2011, 2020, 2024 and 2026 the big explosion of greenery happened as early as the second week, while in 2013 and 2015 it was not till the fourth week, and after the cold April of 2012 it did not happen until the first week of May. In 2021 leafing proceeded more or less as normal in the first half of April, but continued cold weather then put it into slow motion and the treescape was not widely green until the second week of May. In 2018 a cold start to the month and then hot weather mid month meant everything happened in a rush in the third week.
The first leaves on shrubs
The very first new leaves appear way back in winter. As well as evergreens such as holly and yew, some deciduous plants never entirely lose their foliage - for example privet and buddleia - or start putting out new growth as early as December or January - for example honeysuckle. The new shoots on buddleia grow to about two thirds of their final size during March and then finish the job in the first half of April. Honeysuckle foliage is usually complete by the first or second week of April.
Garden privet, the familiar garden hedge plant, which has more rounded leaves, also adds new foliage in March, a process that is usually still finishing in the first half of April. Wild privet, which has narrower leaves and grows in woods and hedgerows, as well as on downland, can be at an earlier stage, and some (particularly on downland for some reason) can even be entirely bare at the start of the month. Most are still not in full leaf until the second half.
Bramble for the most part also keeps a few leaves over the winter (at least in shadier spots: out in open fields it goes almost entirely bare) and as early as mid March puts out new leaf shoots from the middle of its stems. These new leaf shoots can be quite tentative in the first half of April and they often don't reach full size until the second half. Being so widespread, they contribute a lot to the greening of the landscape.
A much less common plant that can be mistaken for bramble is raspberry, which has similar foliage but stems that grow upright (rather than horizontally as with bramble) and which are only slightly prickly. Its leaves emerge pretty much on the same timetable as bramble - ie first shoots from mid March onwards, with leaves reaching full size by mid April. In the second half of the month it may even put out flower buds.
Another big contributor to the greening of hedgerows and woodland understoreys, is hawthorn, which is often full out, or nearly so, right at the start of April, covering large areas with a glorious tide of green. Some of the leaves - particularly on smaller or younger bushes - can appear as early as the start of March, but the main wave of foliage - that is, most bushes bursting into leaf - is usually not till the end of that month (the third week of March in warmer years, as late as the second week of April in colder ones). The leaves remain small for a week or two.
Other less noticed contributors to the greening of hedgerows and the woodland understorey include cherry plum, which leafs once its blossom is over, typically some time in late March, and elder, whose leaves have also been growing slowly since as early as January (and particularly in March) and rapidly grow to full size in the first half of April.
Snowberry - a park or garden shrub, but sometimes found in the wild - starts to put out foliage from the second week in March and usually looks in full leaf in the first or second week of April, though its leaves continue to grow and do not reach their full size for another couple of weeks.
Dog rose also starts to tentatively put forth leaves in March, but its foliage does not usually reach its full size until the second half of April. Dogwood leaves can remain small till the fourth week, but stand out attractively against their maroon twigs.
In hedgerows on chalk soils the climbing plant traveller's joy can have a few tentative leaves in the second half of March, but they have not progressed much by the start of April and the plant is usually not fully leafing till the third or fourth week of the month.
On blackthorn the falling blossom (which can be any time from the first week of April to the first week of May - see April blossom and shrubs) gives way to new foliage, though there can be a short gap between the two in which the bush looks a dispiriting brown mess - though there are tiny green shoots if you look closely. Some smaller blackthorns go straight to leaf without flowering at all, or have lower twigs leafing while the upper ones are still in flower.
The tree sequence
Moving on to trees, the very first to leaf is, perhaps surprisingly, weeping willow, which can put out new leaves and catkins as early as the first week in March, and which shines a bright yellowy green in the landscape. This effect usually lasts a little way into April before it fades to a more normal green. (In 2018, exceptionally, weeping willow did not leaf until the second week of April and never quite attained its normal brightness.). The catkins (which nearly always seem to be yellow male ones) fall shortly afterwards.
Hazel, another important hedgerow and woodland understorey plant, tends to have small new leaves at the beginning of April, having started in mid to late March. They remain very small until the second half of April, however. At this early stage they look almost identical to those of hornbeam, to which they are related. Only towards the end of the month do they start to take on their final, more rounded shape, and even then they may not attain their full size until some way into May.
Hornbeam leaves are usually preceded by a mass of male catkins. Typically this happens in the second half of March, though occasionally there are years when there are very few (eg 2025) or none (2020). Leaves then start to appear about ten days later - usually the first or second week of April, making hornbeam the first source of greenery in the upper levels of woods. Once the leaves are out, the catkins last another week or so before falling to the ground.
While the catkins are still on the tree, one is aware of just how many hornbeams there are in some parts of the south east, for example the Weald: they are not common elsewhere in the country, but in our region there are whole woods of them. Along with the leaves, the almost invisible female flowers appear, drooping at the end of the twig, and towards the end of the month these morph into thin tassels, the beginnings of the tree's seed clusters.
Another large tree that leafs early is horse chestnut, whose brown sticky buds expand into monstrous ovals that look like some weird alien fruit, and then overnight produce limp bright green leaves. Typically this process starts at the very end of March but does not get far, with the leaves mainly emerging in the first or second week of April, and taking as much as two weeks to grow to their final (enormous) size.
Once the leaves are fully grown, the flower spikes start to appear on horse chestnuts. Squirrels eat the flower buds and discard the leaves around them, which is why you sometimes find fresh leaves on the ground. In 2017, 2020, 2024, 2025 and 2026 the flowers themselves came out from the third week of the month: otherwise, they appear at the month's end or in early May.
At the start of April, or increasingly in recent years in the last week of March, Norway maple seems to be bursting into bright yellow-green leaves. But on closer inspection these are flowers, with some leaflets. The tree remains a striking sight for a couple of weeks. Once the flowers go over (leaving a yellow carpet on the ground), they turn into tiny winged seeds and the leaves grow to full size.
Larch can be briefly quite noticeable in early April too. The only coniferous tree to lose its needles in winter, it has already started to put out soft tassels of new greenery in the second half of March. These are often quite small at the start of the month, but explode into a mass of bright greenery in the second week.
Notice also the cone-like pink blooms on larch: these are the female flowers, a floral version of the seed cones they will eventually become. These have also started in March and get gradually bigger as April goes on. The male flowers (seen on the same tree) are yellowish and small, looking like undeveloped buds.
Also at the start of April pussy willows (a common name taking in goat willow or sallow and grey willow) are at the height of their catkin phase. There are two types of tree. Males mostly lose their yellow catkins either at the end for March or in the first week of April; leaves then appear, though they remain fairly small all month. Meanwhile female trees have green catkins and small leaf shoots all month. Towards the end of the month the catkins might start producing their fluffy seed.
Another willow - osier, which grows by rivers - has similar male catkins to pussy willows, though more neatly arranged and densely packed on the branches. Once its catkins fall, it puts out clusters of long thin leaves. Like pussy willows, its female trees retain their catkins till early May, when they seed and fall.
Much more common than osier in the south east is crack willow, which also often grows by rivers. It puts out catkins and small leaf shoots as early as the start of the month, the male catkins yellow and sometimes looking like curly caterpillars, the female green. The male ones often fall to the ground later in the month, but may last some way into May; the female ones remain on the tree. The leaves remain small all month.
The very similar white willow has less glossy and slightly darker leaves than crack willow, with a slightly hairy underside, and its new twigs are brown while those of crack willow are yellowish (though the two species do also interbreed). It slowly puts out leaves and catkins during April, both male and female ones looking green at this stage and so being hard to tell apart, the texture of the female ones a bit more like a cluster of seeds. Later in the month the male catkins may start to turn yellow. As with crack willow, the leaves remain quite small even at the end of April.
In the first or second week of April (or even at the very end of March: it seems to be quite variable from tree to tree) the short brown catkins that have hung on birch trees all winter lengthen out, causing big problems to hayfever sufferers (birch pollen is very allergenic). The leaves generally appear at the same time, though on some trees they are a bit later: they then grow at varying rates, with some trees greening up quite quickly. The catkins last until late in the month or sometimes into May, but in truth it is quite hard to spot when they finally fall off because there are more interesting things to look at.
One is sycamores. A few saplings and smaller trees that are not going to flower may have started leafing in late March, but at the start of April most mature trees are still just showing large green buds. They can be surprisingly slow about bursting into leaf and the timing of this can vary greatly from tree to tree - anytime from the start to the end of the month, basically, with nearly bare trees not uncommon even at the month's end.
Once they do decide to stir themselves, sycamores put forward very alien-looking shoots (they rival in weirdness the ones on horse chestnut), which resolve themselves into tassels of flowers that hang down like bunches of grapes, and leaves that sometimes look brown and autumnal when they unfold. They may then grow to full size only slowly.
Field maple (our only native maple species) also produces flowers and leaf shoots simultaneously, the flowers initially being more prominent. This happens usually in the second or third week. The leaves are initially small and hang limply, as if drying out, but may grow bigger more quickly on saplings and hedgerow plants that are not going to flower.
Poplars - both hybrid black and lombardy types - have already produced their fat maroon-coloured catkins in March. After the catkins fall, there is a bit of a pause and then in the second or third week of April (the first week in 2026) the leaves appear - olive-coloured or even red-brown initially on hybrid black poplars, where they slowly turn green as the month progresses; sometimes slightly olive on lombardy, but very quickly turning green. Western balsam poplars - traditionally used as windbreak trees in orchards or hop gardens - have had foliage since March and may still have green (female?) catkins.
London plane, more of a street tree than a rural one, puts out new globular flowers in the second week (from the start of the month in central London, and more widely in 2024), the larger female ones hanging down from the tip of the twig, and being sometimes quite red but otherwise a sort of rusty brown or olive green; the male ones small, green or yellowy-green, and a bit further back on the twig. Towards the end of the month the male ones turn fluffy and fall, while the female ones get a little bit larger.
London plane leaves appear at the same time as the flowers, but generally remain small until May (the tree looks a mess while they are in this state). You can also see quite a few of last year's brown seed balls still on the twigs, which may fall and break apart producing piles of silky tassels on the ground, though the timing for this is very variable.
Other trees leafing mid month include alder, lime and rowan, the latter easy to mistake for ash due to its similar foliage. On alders and limes these leaves can remain very small till well into May. The lime ones look a bit like teardrops when new.
Elms are still in flower at the start of the month, and by mid month have bunches of their flat seeds. The ones you see are overhelmingly likely to be wych elm, which is in fact our native species, as English elm is generally only a hedgerow shrub these days due to Dutch Elm Disease. The seeds seem to remain on the branches for a good while before the leaves start to come through at the end of the month, remaining rather small until the seeds fall in May. Once developed, a sharper point to the leaves distinguishes wych elm from English elm.
One of the stranger tree sights of April are the pale leaves of common whitebeam, which unfold from an upright centre like tulip petals from the second or third week, and are very prominent in the landscape by virtue of their greyish (or silvery?) tinge. They can remain fairly small all month, however, still in their tulip-like clusters even at the month's end. Greyish flower buds appear but (apart from in 2026...) don't bloom until May.
The kings of the woodland
You might say that all of the preceding shrubs and trees are the warm-up acts for the big event, which is when oaks come into leaf. They are such a dominant tree that they turn whole swathes of the countryside from brown to green. You could claim, indeed, that this is the moment when winter is finally banished from the landscape.
Oaks produce leaves and yellow-green tassel flowers simultaneously, but the leaves are slow to grow and the flowers dominate to begin with. You have to look closely to see this, however, as from a distance the flowers look like new foliage. On trees with no or fewer flower tassels, the leaves grow more rapidly.
All of this usually happens either in the second or third week. This at least is when the big wave occurs, but oaks are particularly sensitive to temperature, leafing eight days on average earlier for each degree rise, while ashes only leaf four days earlier, and - as is perhaps not surprising, given their long lives - they seem to have their own particular responses to the micro-climates they live in. It is therefore not unusual to find one leafing a bit earlier, or only just starting at the end of the month (which is when all oaks started in cold 2013).
Another very striking tree contribution to the treescape is from beech. While some leaves may be seen from the second or third week of the month, the main wave of new foliage is typically not till the fourth week, or even the first week of May in colder years. Some large trees further north (eg on the Ashridge estate near Tring) or high up (eg on top of Leith Hill in Surrey) may come out quite a bit later than the main mass. Leafing is accompanied by the appearance of male flowers, though this is very variable - lots some years, almost none in others.
When new, beech leaves seem incredibly bright and hang in limp lines like washing hanging out to dry, making them one of the more breathtaking sights in the woods, particularly when backlit by the sun. Their appearance often coincides with the fullest phase of the bluebell season, the luminous green leaves providing a brilliant backdrop to the purple-blue of the flowers.
Beech hedges also make an amazing switch. They keep last year's brown leaves all the winter but at some point in April dump them and put out bright green new ones. Unless you have one in a street near you, it is quite hard to catch them in the act: they just seem to change overnight.
By this point most of the bare trees you see are ash. It puts out its strange flowers - looking like frizzy lettuce - in late March, meaning they are at their best at the start of April. There are in fact two types - the more compact male ones and the female ones which are already flecked with the seeds to come, though it is only as the latter grow larger that the difference becomes obvious.
Birds such as wood pigeons and blue tits enthusiastically peck away at both types of flower. Within a week or two the male flowers fall to the ground while the female ones lengthen into feathery fans and slowly become more seed-like.
From a distance these seed fans can make ashes look as if they are leafing, but mostly they do not actually do so until the very end of April, the first week of May, or - in 2012, 2014, 2016, 2019 and 2021 - the second week. Even in normal years their foliage can remain tentative until late in May.
Exceptions to this were 2020 and 2026, when leafing started quite widely from mid April and leaves were mid-sized at the end of the month. Also 2024, when female flowers were scarce and many female trees put out small leaves from mid April, though they did not grow very large by the month's end.
One other laggard is sweet chestnut, which mostly does not leaf till May, though towards the end of April you may see some small leaves, particularly on saplings or trees that have been coppiced in the not too distant past.
More April pages:
- Intro and woodland flowers
- Verge and field flowers
- Blossom and shrubs
- Birds
- Butterflies and insects
- Weather
© Peter Conway 2006-2026 • All Rights Reserved
1 comment:
Interesting article and very detailed - thank you.
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