This week’s real excitement is nothing to do with gardens but is the fact that, in the middle of March, the Chinese government quietly started issuing tourist visas again; we are off to Wuhan to meet our nearly-one-year-old grandson for the first time, at the end of this month!  Going to Edinburgh to get said visas meant, of course, a chance to visit the Botanical gardens.  When we went to drop off our passports, the gardens were closed to visitors because of high winds so it’s a good thing I had to go back a week later to pick up the passports with their shiny new visas.

Even in April the gardens have lots of colour to offer, particularly in the rock garden, where many species are native to higher altitudes and flourish in the relatively mild Edinburgh weather.  There are plenty of daffodils, just like Durham Botanics at this time of year, including more unusual species such as the Hoop-petticoat and Cyclamen-flowered daffodils native to the Iberian peninsula.

As I’ve noted before, many of the plants in flower at this time of year are also monocots, from the Lily or Onion families, with their distinctive three or six-petalled flowers and grass-like leaves.  Monocot root structure seems to lend itself to the development of bulbs or corms which allow these plans to grow and flower early in the year, relying heavily on food laid down at the end of the previous growing season.  It should be no surprise, then, that as well as daffodils there are Dog-toothed violets native to southern and central Europe and South American Spring starflowers in bloom now in the rock garden. 

More of a surprise was the Purple Toothwort, growing abundantly around the roots of a small tree.  Native to west and southern Europe, it normally grows on trees such as Poplar and Willow but can grow on the roots of a range of ornamental trees and shrubs.  Like other plants in the Orobanche or Broomrape family, toothworts are holoparasites – they have no green leaves of their own and rely entirely on their host plants for all their needs, tapping into the roots using structures known as haustoria.

Both these toothworts grow out of sight for most of the year as whitish underground stems, covered with thick, colourless leaves (apparently looking like teeth) which remain below ground throughout the plant’s life cycle.  Common Toothwort parasitises Hazel and Alder trees and appears above ground in April, when it produces a spike of dull pink flowers. Purple Toothwort lies so close to the ground that the single flowers seem to appear through a mass of leaf litter.  The generic name, Lathraea, is from the Greek for ‘clandestine’, so having the specific name clandestina in addition seems like overkill!  Toothwort flowers are bilaterally symmetrical, with a prominent stigma which pokes out through the hood made by the fused petals, providing easy access for insect pollinators and making the flowers look a little like aliens from Dr Who, chatting to one another. Once fertilised, Orobanches produce many, tiny seeds, easily dispersed over long distances by the wind, to increase their chances of finding a suitable new host plant emitting the Strigolactone hormones necessary for the seeds to germinate.

Another group of plants flowering well at this time of year are Epimedium and Berberis both, perhaps surprisingly, from the Berberidaceae or Barberry family.

As you might expect from the common name, the berries of many Berberis species are edible; they have a sharp, citrussy taste and are a rich source of Vitamin C.  Zereshk (زرشک), widely used as flavouring in Persian cuisine, are the berries of B. vulgaris, the European Barberry. Whilst Berberis species are found globally in temperate and sub-tropical regions, Epimedium species are mostly endemic to China, though now grown worldwide as ornamentals.  Like most early-flowering plants, Berberis are an important source of pollen and nectar for early-flying insects and advertise this with by producing a sweet, honey-like scent which is much more effective for long-distance advertising than big, brightly-coloured flowers.

Of course, in exchange for providing sustenance for insects, the plant expects to have its flowers pollinated but some insects cheat and avoid the stigma and anthers.  Many of the Pasque flowers in the gardens were looking worse for wear where a nectar thief had cut straight to the chase, chomping its way through the sepals and petals at the base of the flower.

Pasque flowers are a seasonal note on which to end this post, the common name coming from the Hebrew word ‘pasakh’, or Passover.

At the moment I’m reading Making Eden, by David Beerling of Sheffield University– a fascinating account of the arrival of plants on land and the greening of our planet

In my garden the lesser Celandines and native Primroses have been joined by the first of the year’s daffodils as well as lots of cheery Muscari and delicate blue Anemone blanda.

In the allotment I’ve put up my new greenhouse and planted kale, leek, courgette and squash seeds in trays and runner beans in a trough.  Hopefully the warmth will get them off to a good start.  There is no sign of growth from the directly-sown broad bean and pea seeds yet, but I’ve put in onion sets too.

We ate the best avocado on toast I’ve ever tasted, followed by an equally-delicious San Sebastian Cheesecake, at a little café called Krem Karamel, opposite the East gate of Edinburgh Botanical gardens.   Would highly recommend!