A Northumberland Alpine Gardener's Diary
This entry: 21 January 2007 by John Richards
Northumberland Diary. Entry 20.
Cool for Frits
As we enter the final third of January, this continues to be the mildest winter I have experienced in the north-east of England. I can count the number of proper frosts on the fingers of one hand, and the lowest the mercury has sunk so far is -5C. Under (unheated) glass, the temperature has scarcely dipped below zero. In fact it is very unpleasant today, scarcely +2C with a biting wind and scattered sleet, but the mild weather is set to return by the end of the week.
Many alpines give good notice of their future display, and the bud set on rhododendrons, primulas, saxifrages etc suggests that it is not influenced by the lack of cold. Of course, many fine alpine gardens experience little frost even in what passes for a 'normal' winter, Inverewe in north-west Scotland for instance, or John Good's North Wales coastal garden. Also, as yet, few plants seem to be flowering well ahead of their usual season. Snowdrops, crocus, iris, early narcissi etc seem to be roughly on time. Neveretheless, if the mild weather does continue we can expect unseasonal flowers to be subject to threats from cold snaps in the early spring.
One solution is to hold back some subjects artificially. For some years I have kept a small box 'fridge in the potting shed, largely to store seed, and back in September I wrote about my experiences of holding back autumn bulbs for a show. We have just replaced our kitchen fridge, so I have a much larger fridge to play with! I shall experiment with some alpine bulbs, in the hope that artificial chilling will hold them back and help to keep them dwarf and 'in character'. Amongst those I have selected are Crocus pelistericus and Fritillaria aurea. I also hope that Iris 'Katharine Hodgkin', so far only about 1 cm through the ground, could be held back for a show. I shall report back!
Certainly the warm weather has not influenced the flowering of what I received as Narcissus romieuxii subsp. albidus var. zianicus. According to Blanchard this is supposed to differ from romieuxii by paler flowers, mid yellow anthers and white styles. Um! Anyway, like several others it does seem to have a distinctive flowering season which it keeps to every year.
There might be other potential effects from a very mild winter of course. The seed that I sowed some three weeks ago (130 packets in all) has scarcely received a frost. Chilling vernalisation probably doesn't actually need a frost; temperatures below 5C when the seed is wet is probably enough, but I guess frost does help to rupture hard seed coats.
Another effect may be high numbers of pests in the spring. Aphid numbers were low after last years rather hard winter; I would be willing to wager they will be higher in the coming spring! Plants may be more liable to fungal attack too, and more etiolated, which can encourage fungal attack. We will see!
Here is the pretty little Crocus leichtlinii, in full flower now. Several of the very early Turkish crocuses, such as C. baytopiorum, share this sky-blue colour, as do several of the multifarious subspecies of C. biflorus, of which the present subject might well be considered one.
Crevices are all the rage
If you can't beat them, join them! I like crevices as an idea for growing difficult alpinea outside, and I think that some crevice beds are aesthetically pleasing, notably my favourite, Zdenek Zolanek's supeb construction in the AGS garden at Pershore. Others are horrible! I like better the idea of crevices within other structures and I have already discussed troughs in this context.
In the 17 years I have spent in the present garden I have twice built a raised terrace bed, and as the photograph below shows, it is in dire need of a second make-over, as many plants, and especially moss, one of the banes of this humid garden, have grown out of control. I am posting the present photo merely to show the starting point. Over the next few weeks, weather permitting, I intend to rebuild this bed as a crevice garden.
Two petrocosmeas have already graced these pages, and as indicated earlier, P. grandiflora looked set to flower after Christmas, making it the earliest, not the latest species! It is going flat out now and I like it a lot. I wonder how it would manage in a more severe winter? Perhaps we will never find out!
Early Purples again.
When I posted Helleborus 'Early Purple Group' just after Christmas, it was only just emerging from bud. It is the best plant in the garden as I write, so I thought I would show it in full flower. H. odorus is also flowering now, and I may show it next week.