Drought and Humidity; Spawning and Splitting the Mighty Atom; and Growing Down or Up

Last week was the time for Caroline Spelman M.P. and Environment Secretary to gather the movers and shakers for a drought summit. Why? Because many parts of Eastern, Southern and Central England are at risk of severe shortages of water over the summer unless unseasonably high rainfall occurs over the next few months, and now the prospect of hose pipe bans looms for gardeners in these areas after another dry winter.

I love the subtle drift of green into yellow on the reverse of a new daffodil for us, Narcissus “Rijnveld’s Early Sensation”. We’ll definitely grow more of this in future. 19/02/12

West Wales is currently not having to worry about such things. It’s been a little drier than usual over the last few months, but that’s relative, and with an average of just less than 8 dry days per month over the last 6 months, the lack of sunshine has been more of a concern for us. But I’d been thinking about our own battles with the wet (maintaining the external fabric of buildings down here is more of a challenge than in drier regions) whilst internally high humidity means mould formation is never far away. We manage to control internal humidity with several dehumidifiers, and I always know that when we get a blast of cold, but drier air from Siberia for a brief period, the piano behaves itself. The keys move smoothly, the whole action is lighter and slicker and playing it for an amateur like me suddenly becomes a joy. Then the weather changes, and like a sulky uncommunicative teenager, the piano becomes much more challenging. Notes stick, the sound is more dull, the action less smooth.

Our first spring flowering Camellia cultivar (‘Waterlily’) flower opened this week.26/02/12

But as gardeners, would we want to be anywhere else in the UK? I don’t think so. This opinion was reinforced on Friday at the excellent Llandysul gardening event when the first of two fascinating talks was given by the new head gardener from Aberglasney -Joseph Atkins. With experience gained in several other areas of the UK, he extolled the virtues of wet west Wales, in allowing us to grow a huge range of plants, particularly those from the higher altitudes of S.E.Asia. It inspired us to try a few more exotic plants to add to those like Meconopsis which we’ve found fairly easy in this regularly humid environment.

At last a warm day for the Crocus tommasinianus flowers to really open and glow. 27/02/12

The local amphibians – frogs and toads, also thrive in our climate. Most of the year they are occasional accidental sightings, keeping themselves well hidden, but annually in February for less than a week they mass after dark on our access track, to such an extent that driving back after about 9 pm means a slow crawl past literally hundreds of stationery wedge shaped silhouettes in the car’s headlights. I’d forgotten all about this when last week I went out at about this time, torch in hand to check out a distant generator type noise which a friend from over a mile away in the other direction was finding a constant nuisance. It was a very still and quiet night, and I’d slowly walked about 60 yards down the track when I heard an occasional soft squeaking or squelching sound.

It’s strange how, devoid of many external stimuli in this dark and nearly silent environment, my brain quickly worked out that it must have been coming from my old Crocs. Somehow, I must have stepped on a nail and it had allowed air into the spongy base. I stopped and the noise stopped. I started again, and the noise started. But I quickly forgot about it since I was trying to localise the regular mechanical sounds from the far side of the valley. Eventually happy that I’d a fair idea where they were coming from, I turned round and headed back up the hill.

Then at the same point as on the way down, the regular squelching sound started up again. And then I saw the culprit. A frog on the track. But getting closer to it I realised that it wasn’t making any noise, rather another one just outside the main torch beam which was writhing on the ground. Oh dear, again the brain leaped to an incorrect assumption – the frog was mortally wounded having been squashed by Fiona driving home earlier in the day. Wrong again. Turning the beam more accurately onto the sound source revealed a pair of frogs caught in flagrante. Or Amplexus (Latin for embrace) as it is apparently known in the amphibian lexicon.

But why here, on the track? And not in a ditch or pond? Wet though the climate is, from this point to the nearest pond would be several hundred metres. After a bit of googling and reading I discovered that there are several recognised frog grasping positions for amplexus (and not surprisingly it’s always the male that does the grasping). That it can last for hours or even days, and that some males are so desperate they’ll grasp anything with a vaguely frog like shape. And hang on for hours. The strange sound I’d heard is just one of a diverse range of frog and toad vocalisations which have been widely researched.

Torch lit ampilplexus on the track, sorry for the poor quality! 23/02/12

After only managing a very poor photo to record the event (plenty of time to dash home, grab the camera and return, but sadly the flash misbehaved), my guess is that the locked pair sneaked off in an ungainly fashion to somewhere more suitable for the female to spawn, and have the eggs fertilised by the still attached male. But it still didn’t explain satisfactorily to me why the gathering on the track? Surely such ‘foreplay’ would have been safer in the long grass? Whether it was a factor or not, the following night I checked surface temperatures, and the track was about a couple of degrees C higher than the surrounding vegetation. Worth seeking out as a cold blooded amphibian when passions rise?  Certainly it’s been recently recorded that bees in Israel will selectively drink warm nectar when it’s cold, and colder nectar when it’s hot. I’ve no idea whether this is the reason, but if anyone has a better suggestion or the definitive answer, do let me know.

Quite a surprise to see how far the sunrise has shifted to the East since the last one we had. 27/02/12

The high humidity was also in my mind when thinking about the issue of when to lift and split snowdrops, including the aptly named ‘Mighty Atom’ cultivar. I’d already started this annual task about 2 weeks previously after being caught out last year by the very dry March and April. I always wait until the weather is damp, and having no opportunity in these 2 months the chance was missed for 2011.

Togged up for snowdrop splitting in west Wales in February. In the light rain. Notice how the bulbs in this clump beneath a Hydrangea are sitting pretty much flush with the surface, (the white blobs between my gloves),  but still doing really well. 22/02/12

Pulled apart a single clump planted about 5 years ago can easily yield 40 or 50 bulbs for replanting in groups of 3 or 4. These are Galanthus nivalis, but we do grow G. ‘Mighty Atom’, which is always fun to split. 22/02/12

My trusty assistant Fiona braves the rain (with red umbrella) to get some video footage of the bulbs being planted after splitting. If you look at my pages on Insect Friendly Flowers you’ll see that it will take many decades for snowdrops to spread and bulk up by seed, since so few viable seed seem to germinate with many cultivars, and they aren’t widely dispersed like some Crocus or Cyclamen by ants. So to achieve real impact in the garden you have to either keep on buying in, which is more risky because the bulbs are out of the ground for longer and at risk of drying out. Or regularly split the clumps that you already have. After 25 years of doing this in 2 different gardens we now have so many clumps that they create a fantastic display, and also such apparently brutal behaviour in the middle of flowering time doesn’t now wreck the overall display. Perhaps only 1 in 4 clumps will be split each year. I reckon in a couple of years it will be my knees, or the lack of planting space,s which will limit this process, and not a shortage of snowdrops. What a slog! 22/02/12

Of course the conventional expert opinion is that moving snowdrops ‘in the green’ weakens the bulbs, and that its better to wait until they’re dormant in July or August. But the trouble is that by then when the foliage has died down how do you find the clumps? And even if they were marked in some way, how do you know where to snuck them in between other bulbs or plants for a pleasing natural effect? And what about all the other luxuriant foliage which will get trashed as you plunge in between herbaceous perennials in full flow and into what will also be harder and drier soil?

The amphitheatre snowdrops after ‘the splitter’ has harvested this year’s takings. 26/02/12

More Snowdrops, Helleborus hybridus, Crocus tommasinianus and Pulmonaria longifolia. 26/02/12

No. For us I think that earlier is better, and if it means you lose a bit of this year’s flower display, just remind yourself how much better things will be next year, with the extra clumps spread around the garden. Perhaps for those without the advantages of regular soft Welsh rain, then watering the ground before lifting at this very early time of the year, and again after splitting and replanting if the weather continues to be dry for a week or two, would be a sensible insurance policy. At least in February other plants are only just starting to use soil moisture, and the sun’s strength if it appears, is for fewer hours than in March or April. I’m going to slot in a few general pictures here, and the final bit of the blog will look at similarities and differences between Crocus and snowdrop growth and development, but is perhaps only for those with too much time on their hands, like me?

Cranes, Waxcaps, Snowdrops and Shadows. Magic Terrace Garden. For the real image see below… 19/02/12

Crocus ‘Snow Bunting’ in the copse 27/02/12

A serendipitous and pleasing association of Iris reticulata and Crocus tommasinianus 27/02/12

Crocus tommasinianus, Scilla tubergeniana and Cyclamen coum 27/02/12

For this week’s blog silhouettes this is a Greater Spotted Woodpecker. The top of this larch tree is a favoured calling post, and it wasn’t long before the woodpecker was ousted from pole position… 23/02/12

Beating a hasty retreat …

… before a Carrion Crow arrives.

Several years ago, I’d wanted to add a bit of interest to our clumps of autumn fruiting raspberries, which like many plants in our ‘matrix’ fruit and vegetable garden are planted in an old tyre. The system worked so well that a second tyre layer was added a few years later, but unfortunately the snowdrops, having died down in the summer were forgotten about.

Quite a climb for the snowdrops to get from the middle of the lower tyre to where they are now. So how do they do it? 24/02/12

So they now ended up at least 10 inches deeper than their original planting positions. But by this year they’d clumped up so well that I thought I should try to split them. With a bit of effort, I eventually managed to prise several out from amongst the raspberry roots. And this is what I found:

Several of the snowdrop bulbs removed from the ‘raspberry’ tyre. 25/02/12

Cleaned up, its a bit clearer that these snowdrops have started 2 separate bulbs with independent roots at about 2 inch intervals up the ‘stem’….except in a snowdrop the ‘stem’ is of course the leaves of the bulb. The real stem is inside the bulb itself and forms the basal plate. – see image below. How long it’s taken for the bulbs to achieve this upward progress through the soil I don’t  know. 26/02/12

Most of the bulbs had produced new bulbs a couple of inches higher up the ‘stems’, with roots attached. Several of the bulbs had done this again a further couple of inches higher up the ‘stem’. So the bulb clearly has a strategy to raise itself from the depths, which is a worthwhile thing to do to escape from being buried too deeply. But how is it doing what seems very similar to the natural air layering of the stem of an old Clematis viticella ‘Blue Belle’ which I also rejuvenated this year?

All these roots were produced in fresh air from a thick Clematis viticella ‘Blue Belle’ stem (hidden away amongst honeysuckle stems and shade to the East by a low wall a couple of feet off the ground) because of the high and consistent humidity here. The section of stem has yielded several viable cuttings like this one. 24/02/12

Because of course the snowdrop is creating the new bulb from the leaves, and not a stem. And bulb growth and development occurs from the basal plate which can be seen in the subsequent images. This basal plate is the equivalent of a normal plant’s stem, and the leaves therefore derive directly from the top of it, whilst the roots originate from it’s base.

Section through Snowdrop bulb (left), and Crocus corm (right). The basal plate of the snowdrop is a slightly creamy straw colour. The layers of the snowdrop bulb are formed from the remains of previous year’s leaves. 25/02/12

And how does the ‘stem’ or basal plate know that it needs to move higher in the ground so better make a new bulb higher up. And then repeat the process higher again? Everything I’d read before thinking about this conundrum implied that all growth in a bulb was controlled from this basal plate region. But it seems that what I’ve described must require some sort of chemical feedback from the leaves to stimulate the new bulb and root formation so far away from the original. Sadly I couldn’t track anything down on this subject or other images of what I’ve described, save the following link from John Grimshaw’s blog, (John is a renowned UK Snowdrop expert and co-author of the Snowdrop reference book with Bishop and Davies….” Snowdrops, A Monograph”) where he describes and illustrates the process, but shows only dormant bulbs, and only a single ‘jump’ of the basal plate. I’ve cut the bulbs as shown and am replanting the single and double sections at normal depths to see if at this time of the year they all still have the potential to regenerate normal bulbs in time.

All 9 of these sections have been planted at a normal- ish depth of a couple of inches. How many will be viable next year? I’ll update next January. In the meantime I have an idea for another experiment to look into how the snowdrop manages to do this.  25/02/12

So the poisonous snowdrop bulb is capable of moving up through the soil in this way. Meanwhile the edible (at least as far as many small rodents and squirrels are concerned) Crocus corm seems to be regularly striving to grow deeper into the ground. This seems rational if it is a favoured food of many animals, and because in the case of a corm like a Crocus, the main part of the corm is the swollen stem base, and each year the old stem base produces the leaves and flower, and then at the end of the growing season a new corm which sits on top of the old one. (See above) So Crocus will naturally tend to grow higher in the soil. The Crocus counteracts this by having the ability to produce thick conical contractile roots. These fill with starch during the growing season, then this starch gets transferred to the newly formed corm, and so the root shrinks, pulling the newly formed corm deeper down into the soil. (New cormlets can also be formed at the corm’s base which have contractile roots as well). You can see how different these contractile roots are to the fine fibrous roots of a more mature corm.

4 years from seed to flowering size corm in Crocus tommasinianus- see below for details. 25/02/12

Notice in particular how close the seed of the 2 naturally self seeded seedlings in row 1 were to the soil surface. Next, the 3 left hand second year coms have very fibrous root systems. These were naturally growing in very fibrous leaf litter. The 2 right hand ones have fibrous roots and contractile roots. These were sown as recommended on a respected website, by me at a depth of 2 inches in less fibrous gritty loam. The third row shows similar variations a further year on, with contractile and fibrous roots but by now 2 leaves are produced by each corm . Finally by year 4 a flowering corm with developing cormlet.

The same 4 years for Galanthus nivalis seedlings. But notice the lack of the same dramatic conical contractile root, and also how deep the seeds were in the soil for naturally germinated snowdrops growing in leaf litter beneath a mature Hydrangea. Unlike the parent bulbs which were growing very near the surface as shown above. A single Crocus seedling is shown to the right to illustrate this difference with their seedlings. My question is how do the snowdrop seeds end up naturally 2 inches down in leaf litter, when the Crocus seedling germinates in similar conditions very close to the surface? Ants are often thought to carry seeds down, but we don’t get many ants in these locations. Have the snowdrop seeds just been buried by years of leaf litter? Or moved by worm activity in the leaf litter? So should snowdrop seed also be sown 2 inches down?

Finally, on the theme of snowdrop propagation you may recall my earlier comments in a post on trying leaf cuttings from a ‘Trym’ like snowdrop, from the two leaves inadvertently pulled off a deeply planted bulb. Last night it occurred to me that there’s a probable link between the snowdrop’s ability to produce multiple rooted bulb like swellings along the ‘stem’ of leaves from a deeply planted bulb and its potential to root from a leaf cutting. As you can see from the image below, one of the leaf cuttings is still going strong, and looking healthy over 4 and a half weeks after it was unceremoniously ripped from it’s bulb base. The other 2 cuttings grew well for over 2 weeks and then rotted at the base.

So far success with the Galanthus ‘Trym’ like snowdrop leaf cutting . This image was taken 26 days after the cutting was taken. the other divided leaf cuttings have both rotted. no fungicide was used on the leaves, though powdered rooting compound was. 20/02/12

Of course very few leaves have the capacity to produce new plants in this way – think oaks, rose, clematis, as a few of those which I don’t think can root in this way, but I did find a link to a South African site where there is a brief mention of leaf cuttings from other members of the Amaryllidaceae family, to which snowdrops also belong. It’s quite a clever ability for a plant to have – a bit like embryonic stem cell multi-potentiality I guess, but also raises the issue of what part of the leaf structure controls what’s going on. And also raises the question of how long can I keep a leaf cutting like this growing during a single growing season, but this issue will have to wait for another occasion. If you’ve made it to here, you deserve a medal, but thanks for reading.

Cranes, Waxcaps, Snowdrops and Shadows 26/02/12


5 thoughts on “Drought and Humidity; Spawning and Splitting the Mighty Atom; and Growing Down or Up

  1. Fascinating look at all the stages of growth from both the galathus and crocus. Fingers crossed for your Trym snowdrop, hope it works.

  2. Pingback: Valentine Memories and Slug Graffiti ; Up and Down and Down and Up; Cyclamania and Buried Treasure. | thegardenimpressionists

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