Any digging at this time of year brings out the inevitable Robin seeking something to eat.

 

 There has been a good deal of flooding in Bedfordshire in recent days particularly along the River Great Ouse. I was reminded of this photograph from a couple of years ago. The trig point shown above is the highest point of the Pegsdon Hills and the view is looking out across Bedfordshire.

 I've written a number of entries about this range of chalk hills which are the easternmost tip of the Chilterns. Mainly this is a diary about botany but a bit of geography is noteworthy in this case. The hills form a section of the watershed between the London Basin and the Wash i.e. the rains drain one way or the other. Rain that fell hereabouts will be contributing to the deluge that's heading east across Bedfordshire.

 

 Christmas dinner for the birdies. From late autumn to early summer I put out bird feeders with sunflower seeds, peanuts and fat balls.

 

 The Nasturtiums that carpeted a large patch of the allotment around the bean canes have run their course. They flowered for months and seeded copiously (having grown from self-seeding last year). 

 Nasturtiums are not usually classed as a green manure like Phacelia or Buckwheat but they grow so well on the allotment that they do in effect serve that purpose. The mass of decaying tendrils will add a good amount of humus and nutrition to the soil.

 The humble Nasturtium has edible leaves and flowers, and I gather the seeds can be pickled in brine when still green. It's reckoned to be a good choice for companion planting, attracts bees and makes for a moisture retaining weed suppressing groundcover during the growing season. And a green manure/mulch at the end of the year. Nasturtiums give a lot for very little effort.

 

 We are passing through the Winter Solstice. The shortest day and the longest night heralds the rebirth of the sun. In the garden the first Snowdrops are starting to rise up from the damp earth and decaying leaves.

 

 Stinking Hellebore (Hellebore foetidus) flowers early. The ones in the garden have been flowering before Christmas in recent years. No doubt this is due to London's microclimate and warmer winters in general. Mine are from cultivated stock though it is also a UK native. 

 There are not many plants with green flowers. The flowers and stems of H. foetidus are of a particularly luminous green rising up from rather shaggy foliage of a darker hue.    

 

 Winter Sunshine. That's the name of this cultivar of Mahonia x media. It lives up to its name flowering deep into December. On sunny winter days bees come out of hibernation to forage on the flowers.

 

 Japanese Azalea is a garden centre staple. As such it rather falls outside this diary's interest in native and naturalised plants (though all garden plants have wild ancestry somewhere of course). My father got this one as a free gift with some bulbs he ordered so I potted it up for the patio in a larger terracotta pot.

 It put me mind of a point which I haven't really addressed before. Azalea japonica needs an ericaceous (i.e. acidic) soil. They share this trait with other members of the Rhododendron genus whose plant family is indeed Ericaceae. This diary has its roots in London clay and Hertfordshire chalk so I garden to those conditions and don't seek to change the PH balance of the soil selecting suitable plants accordingly.

 The secret to successful gardening is not really the mystical "green fingers". It's more a case of understanding what conditions a plant needs to flourish. That's also relevant to seeking out wildflowers and particularly relevant if you want to cultivate them. The flora of a limestone scarp is very different to the flora of a a peat bog. Some plants are generalists but most wild plants have a very specific ecological niche. The horticultural trade tends to favour generalists but the Ericaceae includes some popular plants.

 In the case of this little Azalea I found an old pot that had been filled with compost once upon a time. This was probably a standard compost of a fairly neutral PH. However it had been sat under a pine tree for years and was topped up with pine needles in various layers of decomposition which I mixed in then topped off with a mulch of more of the same. Pine needles are acidic so hopefully this will provide a suitable soil. 

 

 Echium pininana is naturalising in warmer parts of the UK, including London as mentioned in my last entry. I spotted these three in the village of Abbotsbury in Dorset; in fact they were popping up all over the village. The village also has palm trees and is home to the Abbotsbury Subtropical Gardens so the climate is conducive.  E. pininana is triennial, this trio are in the second year of growth. 

 

 The ones above are in St. James's Park in their third year of growth living up to their common name of Tree Echium and studded with thousands of blue flowers.  They are also known as Giant Echium and Giant Viper's Bugloss (being a relative of our native Echium vulgare which grows to only a foot or two tall).

  This is an Echium wildpretii which I grew in my front garden from a seedling given to me by one of the gardeners at the South London Botanical Institute. It flowered mightily this year.

  E. wildpretii is sometimes called the Tower of Jewels and is a relative of the Tree Echium on the Canary Islands. The two species hybridise in a form that is known as Pink Fountain, it's possible the one I grew was this variation. Perhaps Towers and Fountains will start naturalising as well.

 Triffids on the march! I have noted in several other entries that Echium pininana is naturalising in parts of London (for example in St. James's Park, see entry dated 14 June 2019). Strange to say some of the best specimens I've come across are in next door's garden. 

 It's a long way from the natural habitat of E. pininana in the Canary Islands but they self seed readily and grow vigorously despite the garden being rather shady. They are called Giant Echiums/Tree Echiums with good reason; in previous years they have grown as tall as the first floor windows.

 

 The Sycamore (Acer pseudoplatanus) at the back of the garden is hanging on to its last leaves. London is generally a week or two behind on the leaf fall and Sycamores are one of the last trees to shed their leaves in autumn. 

 

 Lichen is a composite organism created by the symbiotic relationship between algae or cyanobacteria and fungi. This gatepost I came across in Dorset was becoming encrusted with lichen as though some extraordinary metamorphosis was taking place. And in a way it was.

 

 Mention of moss and lichen in my last entry reminded me of a green lane in Dorset I once walked along... 

  

 

 Green roofs and vertical gardens are in vogue at the moment. This cabin I built about fifteen years ago now has a thick coating of moss on the felt and a mass of ivy growing up one side. I remarked to someone recently that was my idea of a green roof and a vertical garden!

 I was half joking but I do have misgivings about the green roof/vertical garden concept. A certain amount of soil is needed which has considerable weight (especially when wet) and water retaining soil in contact with the exterior of a building may transmit damp. Then again the soil will dry out quite easily so will need a lot of watering at times. These are technical problems which can be addressed but to be honest why go to all the trouble/expense of trying to attach soil to buildings?!

 There are plants that go in the ground that want to climb up walls and any roof in a damp country like Britain starts to green very quickly with moss and lichen (fascinating and valuable in their own right). The cabin wasn't built with a green roof or a vertical garden in mind but nature has taken care of it.  

 

 Rewilding is a topic that's generated a lot of interest recently but is generally spoken of in terms of large areas- country estates for example or tracts of the Scottish Highlands. I've long been intrigued by the idea that back gardens can be havens for nature.

 This diary of back garden botany refers to two back gardens in particular. One belongs to the flat where I live in London, the other to the house I grew up in Hertfordshire (above) where my father still lives. I've spent a lot of time in Herts this year what with the lockdown and one thing and another. 

 When I was a child it was a garden in the more conventional sense: a long lawn (quite sunny) with borders down each side containing a mixture of small trees, shrubs and perennials. As time goes by it has become shadier and -by a mixture of accident and design- taken on the feel of a woodland garden. It's quite sizeable but it's in the middle of town. Yet the depth and variety of wildlife is remarkable. Here are some of the things that have made my heart sing over the course of the year...

 The dawn chorus in spring, incredibly loud. A pair of owls hooting to each other at night. A bird of prey on the roof of the house. A hedgehog snuffling across the patio in darkness. The pond writhing with mating frogs and frogspawn. Bats flitting around at twilight. Bumblebee nests, butterflies on the Buddleia, wasps on the ivy. An eruption of funghi in autumn. A pile of compost crawling with worms. Bugs and creepy crawlies in every nook and cranny.

 So yes, let's rewild the countryside but back gardens can be pretty wild too. The neat and tidy garden is not bereft of nature but let the wildness in and the abundance of wildlife is really quite something.

 

 

 The Nasturtiums on the allotment have been particularly prolific this year as I've mentioned in various entries. I'm starting to gather some of the seed from among the tangle of tendrils. There are many lying beneath and more that are about to drop. I notice that they form in clusters of three. 

 I wrote a number of entries about seed dispersal recently and I should add that plants tend to produce a great deal more seed than is likely to germinate and grow. A single Foxglove for example sheds thousands of tiny seeds. Clearly this is an evolutionary survival strategy.

 Nasturtium seeds are bigger and there are less of them per plant but the same applies. They drop in clusters which puts me in mind of the old tip for growing from seed in pots i.e. plant several in the same pot. One or other of them may not germinate and if more than one does germinate one of them might be a stronger grower.

 NB The seeds are green when they drop. They start to dry out and the hard seed familiar from seed packets is within the pod. 

 The subject of ivy on trees seems to evoke a partisan response. There are those who insist it strangles trees and those who say it does no harm at all, in fact has tremendous ecological value. I have mentioned in several posts recently that ivy is indeed a great plant for wildlife: bugs, bees, birds, bats et al.

 I would think then that this ivy covered oak is an especially good combination in that regard. Oaks are top of the tree (pardon the pun) for nurturing wildlife. Then again I have some sympathy with the idea that a tree shouldn't be entirely subsumed. By the way, this oak was only a few inches tall when my parents bought the house!

 Opposite the oak is a walnut tree where the ivy has climbed to the very top and is spreading out along all the branches. I've made the decision to "ring" the ivy at about head height. Likewise there is a tall and ancient pear tree adjacent to the oak. It used to crop very heavily when I was a child and still flowers a little even now without producing much.

 I rather think the walnut tree wouldn't be adversely affected by ivy for a long time, if at all. So perhaps that's more of an aesthetic decision but my instinct is that the pear tree in its dotage would not be well served by a mass of ivy on the branches. I have also heard it said that voluminous ivy increases the wind profile of a tree and I think there might be something in that.

 There's plenty of ivy in the garden and I will leave it on the oak for a few years yet. If and when I do give it a chop the ivy will be climbing back up the walnut by then. Essentially I don't think there has to be an all or nothing approach though as I say the topic seems to divide opinion.

 NB I wait until ivy has flowered before I cut it back. Where trees are concerned "ringing" ivy seems to me to be preferable to ripping it out altogether i.e. cut the stems all around the trunk (very important not to damage the bark of course). Ivy remains green for months afterwards so any living things overwintering in it will have shelter. The leaves eventually brown and drop off and the stems wither.

 

 The wooden bin I made recently is in situ and I'm starting to fill it with various cuttings, clippings etc. NB The door behind it is simply an old door, it doesn't go anywhere! This will simply be an ongoing pile of "green "waste" generated from around the garden. That is sometimes referred to as "cold composting" i.e. let time do the work. In which case I planned to build another bin alongside to start filling up when the first one is full and gradually decomposing.

 I'm now thinking I might instead make a "hot bin" where the heat of decomposing matter is retained to speed up the process. Wood is not a great insulator so it would need to be lagged, perhaps I could modify a plastic bin? The commercially manufactured hot bins are quite expensive so DIY will be the order of the day.

 Getting the right mix of "greens" and "browns" is important for the hot composting process. I could use material from the cold compost to feed it, also kitchen waste which is currently going into a "Dalek" bin. 

 

 This view looks across the Elmley Marshes on the Isle of Sheppey in the Thames Estuary. I took it some time ago (8th. March 2012 to be precise) and it caught my eye sifting through some old files. Then as now I was struck by the contrast between natural and man-made forms.

 In the intervening period I have taken a number of courses covering aspects of Permaculture taught by Aranya who has a wealth of insight and information on all things permacultural. Seeing the photograph with fresh eyes I immediately connected the image with something Aranya has spoken of. He makes the point that natural forms (like shapes and patterns) are the most effective way of fulfilling a function.

 In this case the flow of water at low tide wends its way through the mudflats following the path of least resistance. Humans on the other hand tend to take the view that the quickest way from A to B is in a straight line (which is often the path of most resistance!). A straight line can be effective in some respects but those of us interested in ecology and the natural world have considerable misgivings about where that straight line is pointing... 

 

NB Aranya's website Learn Permaculture is a good place to start to access some of the teaching resources he has available. 

 Now that's what I call Ivy. Common Ivy (Hedera helix) eventually forms a main stem more like a tree trunk. As I've noted before Ivy is an ecological treasure trove. Ivy in flower attracts around 140 species of insects. Even in early November it still hums with wasps. Likewise the berries are food for birds and Ivy is a food plant for the larvae of certain moths and butterflies, not to mention a habitat for insects, birds and small mammals.

 Having said that I do cut Ivy back because it can be invasive at the expense of other plants. I wait till it has flowered and leave a decent amount of thick growth for wildlife value. In the example shown above I ran a hedge trimmer along all the trailing vines which had completely obscured the wall but left the top knot.  

 

 The Nasturtiums on the allotment are finally subsiding after months of rampant growth. They must have got a breath of frost which always does for them. Even now a few flowers and some foliage remains at the heart of the patch though not for long. They have seeded copiously under the mass of tendrils so they will be back next year.  

 

 Went for a long circular walk today out of Hitchin, taking in Knocking Hoe (above) and the Pegsdon Hills on the edge of the Chilterns. It was summer last time I was here. 

 Now, the low sun raked across the landscape. The folds and undulations of the terrain cast long shadows. 

 

 Knocked up some rudimentary shelves to gather all the miscellaneous pots scattered around the back garden in Hitchin. The timber is more of the salvaged joists I used recently to make a couple of compost bins. 

 

Bare branches, yellowing leaves and red berries. Late autumn becoming early winter.

 A lasagna mulch alternates layers of cardboard with organic matter. This bed had become carpeted with ivy which I dug out. I then laid down a double thickness of brown cardboard recycled from various deliveries. As I have noted previously this makes for a surprisingly long lasting and effective weed suppressant.

 I weighted it down with semi-rotten wood and covered it with fallen leaves. Then added another layer of cardboard with more wood and leaves. As this combination decomposes by fungal action it will merge with (and improve) the structure and biology of the soil.

 In fact leaf mold is not high in nutrients. Commercially produced fertlisers in solid or liquid form are one way of adding NPK (nitrogen, phosphorous, potassium). Alternatively there is a source of well balanced NPK that costs nothing. Yes, I am referring to urine!  

 Out and about today felt strangely like the first lockdown back in March. Eight months later the trees were bare again (albeit with the leaves on the ground) and the weather unseasonably mild and sunny. The constant hum of the city was quietened and the air was still. 

 On a cold and misty morning in London this African Bush Daisy in the front garden defies the season.

 The ground is getting thick with soggy/scrunchy leaves. Where they fall on the beds I leave them be. If they're somewhere I don't want them e.g. on a path I sweep them onto the beds or gather them to make leaf mold.

 There is a regrettable notion that fallen leaves are untidy. Nature is tidy on a colossal scale. Trees grow out of the soil. They drop their leaves which replenishes the soil. Is there any such thing as an untidy forest?

 

 Seed dispersal part four. I mentioned that ants distribute the seeds of Cyclamen hederifolium. I suppose I should include humans as a sub-section of seed dispersal by symbiosis! I sowed Honesty (Lunaria annua) in pots several weeks ago and the first seedlings have appeared already. 

 Left to its owns devices the seeds of L. annua would drop to the ground as the distinctive coin-like seed pods dry out and split open.

 

 The pots contain a mixture of both the purple and white flowered forms of Honesty. They self-seed round and about the garden but I generally grow a few in pots as well. Annuals and biennials make useful gap fillers.

 

 Another photo taken in Green Park yesterday. The colours of autumn are plain to see but central London is something of a heat bubble and I would say a week or two behind the surrounding region. Daylight hours are the principal "on/off" switch where plants are concerned but temperature, rainfall and general climate have a considerable effect. 

 

Walking in Green Park this morning.

 

 Seed dispersal part three. Cyclamen hederifolium does things in a different order to many plants of this hemisphere. It flowers in early autumn, then goes into leaf over winter and loses the leaves in early summer. The exposed coums produce a plethora of seed pods which look rather like tiny coiled springs.   

 The seeds are too heavy to scatter very far but they have a sweet sugary coating which attracts ants who carry them away. Seed dispersal by symbiosis.

 

  Speaking of Comfrey [see last entry] there is a good harvest of it on the allotment which I put in a bucket to steep in water. Comfrey "tea" is said to be rich in nutrients which are released as the leaves break down. 

 This Comfrey is Symphytum officinale or perhaps Symphytum x uplandicum which is a cross between S. officinale and S. asperum.  I can't really tell the difference and Comfreys hybridize readily. The flowers are pinkish-purplish and appear in early summer.

 

 I think this is Dwarf Comfrey (Symphytum ibericum). Beth Chatto describes it as "impenetrable weed-cover" and Martin Crawford calls it "a fantastic ground cover". Certainly this patch on a nearby allotment is holding its own even against couch grass and continues to expand.

 

 This particular allotment seems to be abandoned and I took the liberty of teasing out a few root cuttings for my own allotment. Several sprigs I planted last year quickly formed a large clump -it spreads rapidly by rooting shoots.

 S. ibericum typically has yellow flowers in early spring and looks very much like Creeping Comfrey (S. grandiflorum). Having said that this form has red buds and white flowers that take on a blue tinge. The aforementioned Beth Chatto sells a variety called "Blaueglocken" which fits that description so perhaps that's what we have here.

 

 Seed dispersal part two. Needless to say many plants shed their seed by dropping the fruit straight to the ground. Hence Newton discovered gravity. There is a variation on that; some plants lean over first.

 Case in point the fruits of the Stinking Iris (Iris foetidissima) emerge from the pod as the stem withers. The stem begins to lean and they end up on the ground away from the main clump thus enlarging the potential distribution of the plant. NB I use the word fruit in the botanical sense i.e. the seed bearing structure of a flowering plant. The "fruits" of Stinking Iris are poisonous.