Oregon Grape (Mahonia aquifolium) is a tough suckering shrub from North America often seen blanketing beds in parks and other municipal plantings. It has the virtue of growing strongly in just about any soil or aspect including shade. 

 For that reason it has been used without much imagination. Its natural habitat is in the understory of the forests of the Pacific Northwest and is best utilised in a mixed woodland planting. Blue berries follow the yellow flowers. Foragers and forest gardeners note the berries can be used to make jams and jellies. 

 Wood Spurge (Euphorbia amygdaloides var. robbiae) is particularly vigorous in the garden at the Camden Art Centre [see last entry]. It was part of the original planting back in 2004 and has increased considerably since then. 

 A good choice for shady woodland plantings it has a suckering habit so is known as a spreader. Here it has formed extensive drifts which create a shimmering haze in hues of lime green and acidic yellow. 

 The garden of the Camden Art Centre is a hidden gem of North London. The gallery fronts onto Arkwright Road and alongside the Finchley Road with what is in effect a mixed herbaceous border on a large scale. 

 The garden at the back of the gallery includes a large grassy area fringed by mature trees.

 The lawn slopes sharply to the terrace of the gallery's cafe. The traffic of the Finchley Road can be noisy unfortunately but the greenery of the surroundings is very pleasant.

 When the gallery reopened in 2004 after a period of refurbishment garden designer Julie Bixley was commissioned to develop the garden with extensive new planting. She conceived a woodland garden of shade tolerant species among the existing large trees. The border along the front and side of the gallery gets more sun and the choice of plants reflects this.

 Over the years the planting has been extended and augmented and Julie continues to select the plants accordingly. The garden has evolved and that is ongoing. For example a new walkway is being created from the front of the building to the side entrance which will necessitate some replanting in its wake.       

 I should declare an interest here. Julie roped me in to do the initial tranche of planting with her back in 2004 and I've returned from time to time for some more spade work. I spent four days there last week working my way through a large delivery of plants for various parts of the garden including the new bed above.

 The weather was exceptionally clement, really very warm and sunny considering we are still in March. A very nice spot to work BUT one of the worst places in London to dig a hole! The underlying soil is clay. London clay is very dense anyway but particularly problematic here due to the building works twenty years ago. A lot of excavation took place unearthing a great deal of clay which was dragged back onto the garden area. Any decent top soil and subsoil ended up buried under layers of near impenetrable crud.

 Fortunately you wouldn't know that to look at the garden and as I say it's a bit of a gem.  

 White Comfrey (Symphytum orientale) is worthy of a place in any garden and it's very easy to propagate by root division. I was intending to divide this clump on the allotment but it's already bushy and coming into flower. This is a sunny spot; nearby however there are several in shade which are just becoming leafy so I used one of these instead.

 NB S. orientale flourishes in both sun and partial shade, even quite deep shade. In sun it grows quicker, flowers sooner and is more flowery. In shade the growth is a bit later and the flowers less prolific but they often last longer. I observe this pattern in other plants that are that are adaptable to varying light conditions.  

 The one is starting to clump up with a distinct offshoot from the main root which I sliced off with a spade and planted up elsewhere the same day. It should grow quite rapidly and flower this season forming another clump in due course.     

 I see Three-cornered Leek (Allium triquetrum) all over the place. It was introduced to this country from the Mediterranean (in 1759 according to some sources). The flowers are striking en masse and there's plenty of straggly greenery. 

 I once saw the front garden of a dilapidated house carpeted with A. triquetrum and it was a picturesque sort of a scene. However ecologists have noted that it can be very invasive of natural habitats where it outcompetes and overwhelms native flora. 

 

 Want bees? Plant Comfrey! All Symphytums are bee magnets including the one above which is Symphytum 'Hidcote'. It is said to have originated in the gardens of Hidcote Manor sometime in the first half of the twentieth century, reputedly a cross of three wild species: S. officinale x asperum x grandiflorum.

 Comfreys hybridize readily. Perhaps the gardeners at Hidcote took advantage of this and transferred the pollen from the flowers of one to another in order to create a cultivar. Then again it might well have been a naturally occurring hybrid. No doubt the three species were growing in fairly close proximity and the bees would have done the rest.

 

  An enjoyable session at the South London Botanical Institute updating the inventory of plants in the garden. We last undertook this exercise several years ago and inevitably a few have been lost since then but others have been added.

 The audit doubles up as an event that people can sign up to and take part in. It's a nice way to engage with the garden whether as an expert or beginner. Strictly speaking I was co-leading the proceedings but in the company of Roy and Cath- two people who know a great deal more about the garden than I do. Cath is one of the gardeners here and indeed has planted a good many of the plants we were observing. Listing Roy Vickery's achievements in the field of botany would be a long list!

 Over the course of four hours we managed to tour all of the main beds and amend the existing records as needs be. Spring is in the air and there was plenty to see; I think another session in summer would provide a useful complement to today's observations.

 As I walked along the Icknield Way yesterday I came upon these trees in full flower. Apart from occasional patches of Celandine and Dog Violet nothing else is blooming as yet so I stopped to gaze on the mass of blossom illuminated by spring sunshine.

 Cherry trees flower early and I would think these are Wild Cherry (Prunus avium). This species does indeed grow wild in the UK but was often planted in the hedgerows of old used to divide one field from another. Other natives used for the purpose were the likes of Hawthorn, Blackthorn, Field Maple, Hornbeam and Hazel.

 This particular stretch of countryside is an undulating landscape of very large arable fields. The ancient patchwork of small fields has long been amalgamated into prairies of industrial agriculture. In such areas the trees that remain are often the remnants of hedgerows which are no longer managed and maintained.

 As I stood there I became aware of something wonderful. It was a breezy day but I began to notice a loud and continuous humming noise. The blossom was buzzing with bumblebees! 

 I don't know if I've ever seen so many bumblebees in a single location. There were bumblebees crawling around every branch, coming and going constantly. These will be queen bees emerging from hibernation. It is said that bumblebees will forage up to a kilometre from the nest and the cherry blossom must have been attracting every bumblebee in the vicinity. 

 As I say little else was in flower anywhere nearby so these few surviving cherries must be sustaining the entire bumblebee population within a wide radius at this point in the year. It goes to show how important it is to have even small pockets of planting for pollinators.

Postscript A couple of other species were widely used in hedgerows. Cherry Plum (Prunus cerasifera) and Sour Cherry (Prunus cerasus) might also be candidates for the ones I refer to here. 

 A day like today is perfect for walking- mild and sunny with a gloriously fresh breeze. Accordingly I took a bus from Hitchin to Pirton and headed for the hills. By which I mean the chalk hills where the Chilterns slope down into Bedfordshire. I passed by Knocking Hoe...

 ... then over the Pegsdon Hills. I stopped at the trig point, my usual spot for a flask of hot tea and a cheese sandwich. The Icknield Way -that ancient track from Wiltshire to Norfolk- is nearby. I followed a section of it then turned off at a bridleway to Lilley from where I caught a bus back to Hitchin. A pint sitting outside the Lilley Arms was most welcome.

 Knocking Hoe and the Pegsdon Hills are fragments of a landscape much older than the modern arable fields that surround them. They reveal their past and present in layers like a living palimpsest. 

 Grape Hyacinth (Muscari armeniacum). Native from the Eastern Mediterranean to the Causcus but often grown in British gardens. The bulbs are very cheap to buy in autumn, very beautiful in the spring.

 

 There are several patches of Cardamine quinquefolia in flower at the South London Botanical Institute. Hailing from east Europe I'm surprised it isn't grown more in UK gardens; seems to be vigorous, shade tolerant and flowers early in the year.

 Hopefully I've identified it correctly. It bears a resemblance to C. bulbifera and Cardamine is a large genus. I'm co-leading an event at the SLBI this Saturday to update the inventory of plants in the garden. Fortunately one or both of the SLBI's gardeners will be there too and the renowned botanist Roy Vickery. I'll rely on them for any tricky plant IDs! The event has been well subscribed I believe and should be a nice day for both experts and beginners.

 Postscript 19/03/22  Wiser heads than mine weren't entirely sure which Cardamine this is. So for now calling it C. quinquefolia is a definite maybe, it may be definite. 

 Before and after. The compost bins at the South London Botanical Institute had fallen into a state of disrepair. I set about giving them an upgrade by renewing the front and internal sections with new posts and slats. The contents of the three sections had morphed into one general pile.

 Now it will be possible to generate compost on a three bin cycle. Ideally a composting system has more than one bin. In this case I have consolidated the good composted compost into the bin nearest the camera. The furthest bin can now be filled up ad hoc with garden and kitchen waste, then the middle one. By the time the existing compost has been used up there will be new compost ready to use at the other end. And so it goes.

 Delivery of bare root plants from Shipton Bulbs. Five each of: Nettle Leaved Bellflower, Dame's Violet, Foxglove, the white and red forms of Water Avens, Purple Loosestrife, Monkshood, Marsh Marigold and Solomon's Seal.

 As I've noted before Shipton's bulbs and plants are grown on a smallholding in Wales. They're very hardy and about as close as you can get to actual wild plants though cultivated. They tend to bed in very well; pot grown plants are often pot bound whereas these were lifted from the soil only yesterday.

 The tangle of Mistletoe (Viscum album) on next door's apple tree gets bigger year on year. I'm reminded that the SLBI has a project on iNaturalist to log the locations of Mistletoe across the south of London so I'll add this specimen to their collection.

 Birds eat the berries of V. album but cannot digest the seeds which find a receptive surface on trees with soft bark. There it grows as an obligate hemiparasite i.e. it lives off the host but also photosynthesises. 

Lots of lovely Lungworts in flower at the South London Botanical Institute.

 The compost bins at the South London Botanical Institute are in need of repair and refurbishment. I made a start yesterday...

 

 "Tommies" (Crocus tommassinianus) are sometimes called the Early Crocus and sometimes the Woodland Crocus. Both names are apt: they begin to flower in February and do well in dappled shade when the trees are bare. They need some winter sun for the petals to open wide and reveal the golden orange stigma and anthers dusted with pollen. The straight species (my favourite) has a shimmering silvery-violet hue.

There are other forms with deeper, darker colours like 'Roseus', 'Whitewell Purple', 'Lilac Beauty' and 'Ruby Giant' (shown above- in fact it isn't ruby or giant!).

 

 

 There is also a pure white form. All are variations of the same species but they don't necessarily emerge simultaneously. I have a considerable number of the straight species and 'Ruby Giant'. They overlap but the lighter flowers appear first and the darker a week or two later- I wonder why that is? It's quite useful because it makes for a longer flowering period overall.