As White Comfrey (Symphytum orientale) fades on the allotment another takes its place- Common Comfrey (Symphytum officinale) which has shot up in the past few weeks. Or it may be so-called Russian Comfrey which is a widespread cross between Common Comfrey and Prickly Comfrey (Symphytum asperum).
 I can't tell the difference and they hybridise back and forth very freely. Bees don't make the distinction and make straight for it.

 The patch of wildflower species I planted on an unused corner of the allotment is doing well. Ox-eye Daisies (Leucanthemum vulgare) and Field Scabious (Knautia arvensis) are flowering at the moment:

 Dartmoor. Had a look through the photos I took earlier this month when I went on the course in Practical Forest Gardening at High Heathercombe. These two sights are rather characteristic of the landscape of the moor itself.

 This diary of back garden botany also makes mention of the front garden from time to time. It's actually the sunniest border to grow in but it's not large. Red Valerian (Centranthus ruber) pokes through the railings.

 I have high hopes for this specimen. This is one of the giant Echiums that hail from the Canary Islands. I got it as a small plant from the South London Botanical Institute last year and I can't remember if it's the red flowered E. wildpretii that's endemic to Tenerife or E. pininana from La Palma which has both blue and pink flowered forms. They can grow up to three or four metres high covered in thousands of small flowers. In any case it has put on a thick stem and a healthy rosette of leaves since being planted so the signs are good. Some books refer to it as a biennial but others note that it's triennial i.e. flowers in the third year. We'll see.
 The aptly named Tree Echium aka Giant Viper's Bugloss (Echium pininana) with blue flowers seems to be naturalising in South London and warmer parts of the country so perhaps E. wildpretii will do the same. I posted an entry on 7th. March which shows one of these triffids growing at the SLBI.
 This border is not only sunny but free draining and therefore dry- conditions which suit the various plants that thrive here. Having said that beyond the Echium you will see the silvery leaves of a Lavendula made more silvery by the fact that it's dying. Lavenders are somewhat short lived anyway but it's curious that this one which I grew on from a cutting only a few years has suddenly faded.

 Some plants were knocked back by last year's drought and I think it's fair to say we are in drought now given the meager amount of rain there has been during spring. I wouldn't expect that to be a factor in the Lavender's ill health, being a plant of Mediterranean climes.
 Case in point Purple Toadflax (Linaria purpurea) is from the same region and I have never seen it looking more vigorous. It self-seeds and naturalises all over London and does fine in our climate but this year I notice everywhere it's like a different plant- thicker stemmed, greener, much taller. Clearly the hotter, drier conditions of the past twelve months have suited it.
 It's just coming into bloom now and the spikes of flowers are a treat for the eyes and the bees:

 One of my favourite "invasive" plants. Trailing Bellflower (Campanula poscharskyana) was introduced to the UK from the mountains of the Caucasus as a rockery plant and quickly decided the brick, stone and concrete of London was just like home.

 It spreads, sprawls and scrambles at the front and back of and back of the house without doing any damage (it has to be said that some invasive species can create problems in that regard). Like many prolific plants it is often treated as a weed but the masses of pale blue flowers in late May/early June are glorious. Ironic that C. poscharskyana is also sold at garden centres- here there's a couple of hundred pounds' worth growing free of charge!

 Both bumblebees and honeybees love Trailing Bellflower and the profusion of flowers is ideal for them, not only at this house but up and down the street and all over town. 

 Starting to see the first butterflies in the garden. I feel there has been a substantial decline in London's butterflies (more so than bees) but last year's long hot summer seemed to benefit them and perhaps the warm, dry spring is having the same effect.

 Sometimes called Sweet Rocket, sometimes called Dame's Violet: Hesperis matronalis is a biennial/short lived perennial that has both white and pink flowered forms which sometimes cross pollinate to create a variant in subtle shades of lilac.
 The white form is dominant in the garden this year. Some years ago I planted H. matronalis at the back of a border and like plants often do it has wandered towards the light- by seeding itself into a more favourable position.

 Numerous visitors at the Open Gardens last weekend asked me to identify this plant in particular. I remarked several times that it doesn't seem to attract bees but is a noted butterfly plant (as seen in the pic above which I took last year).

 And then today I saw it being repeatedly visited by a large bumblebee or perhaps several of the same species (Bombus terrestris I think).
 Sweet Rocket aka Dame's Violet is luminous in full sun and seems to glow at twilight. It's one of those blooms that becomes especially fragrant as the sun goes down.

 Lamium orvala and Silene fimbriata always catch the eye of visitors to the garden. Lamiums like the White Dead-nettle (L. album) and Silenes like Red Campion (S. dioica) are widespread as common wildflowers. They're perfectly good as garden plants in my opinion and I made a point of introducing them to mine- they pop up in many gardens whether invited or not!
 L. orvala and S. fimbriata are rather unusual however. The former is native to central and eastern Europe and the latter to the Caucasus. Plant breeders have noted their distinctive appearance and started cultivating them in the UK. They flower happily in dry, shady areas in late spring/early summer which is always a tough spot to choose plants for.
 They're still not widely available and have been pioneered by some of the more specialised plant nurseries. These tend to be smaller but more innovative than those growing on an agricultural scale to supply garden centres and the horticultural trade.  I bought the ones above from Pineview Plants who are one of the mainstays of the Plant Fairs Roadshow which I mentioned in my last post.  

  I am addicted to plants. The first step is admitting you've got a problem. I keep meaning to cut down but then I have a relapse.
 My neighbourhood's annual Open Gardens took place over the weekend. Around thirty gardens took part and I opened the garden on both days. Saturday was busy, Sunday quieter. I'm happy to report that most visitors liked what they saw.
 The local community centre hosts a plant fair on Saturday afternoon which coincides with the Open Gardens. The Plant Fairs Roadshow is akin to a Farmers' Market for plant nurseries. They stage a number of events every year in London and the southern counties of England.
 I have tremendous respect for these specialist independent growers. They grow first rate stock -including many rare and unusual plants- which they sell at reasonable prices. So it was that I came away on Saturday laden with plants. 

 As late spring merges into early summer it seems like a good point to take stock of the year so far. Snowdrops bloom at the end of the garden during February, hard to say how many- a thousand, probably more? A colony this large must have taken at least decades to grow to this size. I've extended it by digging up clumps after flowering and re-planting them but I wonder just how long the Snowdrops have been here?

 I've naturalised several varieties of daffs in the lawn (well, grassy area) to give a splash of cheery colour early in the season. Narcissus February Gold flowered very early in the month. London winters are mild anyway and this one particularly so.

 "Tommies" (Crocus tommasinianus) are a simple joy. They multiply freely and each year I add more. Hundreds flowered simultaneously in February undeterred by a brief cold snap. Glorious and manna for early bees that took to the wing when the weather warmed up again.

 Speaking of bees the White Comfrey flowered early and flowered long. Bees love all Comfreys and by growing several kinds it's possible to have one or more in flower from early spring to high summer.

 Self-seeders pop up where they like which I'm very happy to encourage. I seeded Honesty in the back garden some years ago and this year the biggest, pinkest most flowery one I have ever seen took up residence in the front garden.

 I'm fond of rampant invasive plants. I want to see plants not bare earth. Case in point two patches of Greater Stichwort have gone mad this year. A plant of hedgerows in the countryside it took readily to the garden when I planted a few sprigs of it.

 Apple blossom time is a sure sign that spring is in the air.

 So too the blossoms of Hawthorne tell us that the Maytide is here.

 The garden is looking very lush and green. The flowers of spring are starting to fade and the blooms of summer starting to appear. Who knows what the weather has in store but these are tough, hardy plants (mainly wild species) which take most things in their stride be it drought or downpour.

 The four day course in Practical Forest Gardening which I went on at the beginning of May has been the subject of a number of entries over the past fortnight. In particular I have covered the visit to Martin Crawford at the Agroforestry Research Trust in several posts. I thought I would round things off by saying a bit more about the rest of the course which was based at the High Heathercombe Centre on Dartmoor.
 A bed was available in dorm style rooms at the centre but that would have been too easy so I camped in the grounds (and was woken most mornings by the sound of a woodpecker in the trees nearby). I have a new tent I wanted to field test; seems like a good purchase but I discovered that my self-inflating air mat has become a self-deflating airless mat.
 Chilly at night but the morning shower was hot and the centre a very comfortable place to be- I must make particular mention of the food which was superb. 

 The tutors at Heathercombe were Aranya and Caroline Aitken. I did my PDC (Permaculture Design Certificate) with Aranya a few years ago and several other courses since then. I have noted before in this diary that he is a gifted communicator who can unpick complex subjects with great clarity. 
 I hadn't met Caroline before. I knew she is very highly regarded in the permaculture community and sure enough the content and style of her teaching is excellent. Martin Crawford was the third tutor on the course in the form of the session at A.R.T.  He can talk for hours and every word is worth hearing.
 Most of the theory sessions at Heathercombe took place indoors but on the last day it was warm enough to sit outside.

 The practical element was provided by doing some actual planting of Heathercombe's developing forest garden. Part one of the course in February was concerned with the canopy layer and we planted various trees and shrubs back then to extend the existing garden. Part two concentrated on the understory i.e. the herbaceous perennial and groundcover layers. Here we underplanted trees that are seven years old in keeping with forest gardening's layered approach to growing edibles and other useful plants.
 We packed so much into the four days that we really had to force the pace at the end to achieve all the planting we wanted to do (plus a thick layer of mulch). There was a great bunch of people on the course and everyone piled in to get the job done. 

 An eruption of flowers is on the way in the garden. Geranium x oxonianum is a prolific spreader and self-seeder which clumps up with semi-evergreen foliage and masses of pink flowers (delicately veined in darker pink).
 I've let it spread where I want it and pulled it up where I don't. The first blooms are appearing now and soon they'll be smothered in them. June is their peak but they continue flowering well into September. Bees abound all day long.

 A.R.T. part three. Martin Crawford is honest (and philosophical) that not everything at the Agroforestry Research Trust works out quite how he anticipated. Case in point he devised an irrigation system which worked fine- for a while.
 The various structures like the greenhouse are at the lower end of the site and rainwater off the roofs is collected then pumped uphill by solar powered pumps. At the top of the site the water passes through a large filtration tank then into several large reservoirs. The water gravity feeds through pipes as needed onto the site as a whole.
 It all worked according to plan for several years then the membrane used to line the reservoirs began to perish and leak. Actually it's all too common that products and materials don't last the way they should but it means that Martin has to re-make the reservoirs.

 A few set-backs are inevitable but the scale of Martin's achievements is remarkable. The Littlehempston site is where he has his nursery beds to grow trees and shrubs for both the Trust itself and to sell. He uses no chemicals and improves the soil by alternating growing areas with areas given over to "green manure" cover crops for a year or two, as above where he has sowed Black Medick and Phacelia.

 Martin does all his propagating in two polytunnels from seeds, cuttings and division. A lot of commercial plant nurseries buy in plug plants and grow them on but he does it using the classic methods of botanical horticulture. The potted perennials are laid out alongside the polytunnels awaiting sale or use.
 Many garden centre plants are mass produced in "optimum" conditions i.e. kept in polytunnels, overfertilised, sprayed regularly and too tender to resist pests, disease and weather. By contrast the plants that Martin Crawford grows are clearly very healthy and hardy.
 The working environment at A.R.T. is a utilitarian one. As far as I can see no attempt is made to prettify it but everything large and small is there for a reason.

 Martin Crawford plays a long game. On the way out I went to have a look at a planting of six Monkey Puzzle trees that he had referred to earlier in the day. Monkey Puzzles are dioecious i.e. there are 'male' and 'female' trees whereas the great majority of flowering plants have both 'male' and 'female' flowers on them for the purposes of pollination.
 An edible nut is produced by the female of the species but you don't know if a tree is male or female until it's at least twenty years old!  

 I found myself in Norfolk overnight attending the twentieth anniversary dinner of a company I've done a lot of work for over the years. Admittedly I featured more in their first decade than their second but it was nice to join in.
 Reader, there was revelry and a certain amount of drinking involved. I shall not write of such things but it falls within the scope of this diary to note that the venue was a fine old country house with walled gardens, a croquet lawn and sylvan glades.
 I rose early this morning and wandered down to the boating lake where I lingered awhile in tranquil contemplation. Then I returned to the house in search of strong black coffee.

 I saw this little plant growing out of mossy stones and stumps all around Heathercombe. I was trying to think which rare native flora it might be. Then the penny dropped- it's Pink Purslane (Claytonia sibirica), a plant from North America and Siberia that has naturalised in parts of the UK after being introduced as a garden plant.
 I have it in my own garden! But I didn't recognise it at first because it looks so thoroughly at home in the surroundings, much more vigorous, larger flowers and pinker in fact. Some plants like it tough; anything with the word sibirica in it is invariably very hardy. Dartmoor obviously suits it more than South London.

 A.R.T. part two. After Martin Crawford showed us the forest garden greenhouse he took us round the rest of the site.

 Adjacent to the greenhouse he is developing a low growing garden using forest gardening principles -without the tree canopy- as a prototype for smaller gardens. Living in London that's an approach I find particularly interesting. There is little scope for planting fully fledged forests in urban areas but there are many domestic gardens and public spaces.
 Strawberry plants carpet the ground; there isn't a patch of bare soil anywhere.   

 The Littlehempston site is exposed to the elements (that's the edge of Dartmoor on the horizon). Two forest garden staples form long hedgerow windbreaks: Sea Buckthorn (Hippophae spp.) and Autumn Olive (Elaeagnus umbellata). The former bears berries rich in vitamin C, the latter dark red fruits that can be eaten raw or cooked. Both are valued for their nitrogen fixing properties.

 

The hedges provide some shelter for several large scale plantings. The top photo shows the start of a new forest garden canopy layer. The yellow flowered Brooms are 'nursery plants', which Martin notes is a strategy used in forestry but not agriculture. Shrubs create shelter while the trees establish themselves.
 The second photo shows a planting of hazel in wide rows that will allow for 'alley cropping' i.e. combining agroforestry with polycultures of crops in strips. Elsewhere there are plantings of a nut orchard and experimental coppices i.e. trials of trees that are food producing and suitable for coppicing and pollarding. Martin is something of an authority on nut trees but points out there is no point planting them for food production in a locale where there are squirrels!
 The Littlehempston site is also where Martin does all his propagation and runs a mail order/internet business selling forest garden plants. Part three to follow...