What do you think ?
The directional growth of an organism in response to gravity. Roots display positive geotropism when they grow downwards, while shoots display negative geotropism when they grow upwards. Also called gravitropismsource: The American Heritage® Science Dictionary 2002
It is also defined as:
the response of a plant part to the stimulus of gravity. Plant stems, which grow upwards irrespective of the position in which they are placed, show negative geotropismsource: Collins English Dictionary 2009
So why is the gardener throwing fancy nouns all over the landscaping blog…?
In very simple horticulture and specifically it’s relevance to you – here’s my breakdown of the above definition, for you….
if one should plant a bulb upside down – the roots will always grow south or upwards and the stem will always grow north or downwards. Fact.
In really simple terms, there is no incorrect way to plant a bulb or seed.
So why then do I see this on so many gardening blogs and websites…?
Plant the cloves the right way up! – like any other bulb, if it’s planted incorrectly they will never see the light of day – literally. The base of each clove should be pointing downwards while its peak should face the sun. Fairly obvious, one would assume, but the number of people who ask the question illustrates the need to make the point.
The video below is really terrible… but scroll, to about 30 seconds on the timeline and watch it until the end. It explains it extremely well.
The same theoretically applies to any plant, tree or shrub. This definition should not be confused with phototropism which is a plants stimulus or response to light.
A little further explanation…?
Plants can sense the Earth’s gravitational field. Geotropism is the term applied to the consequent orientation response of growing plant parts. Roots are positively geotropic, that is, they will bend and grow downwards, towards the center of the Earth. In contrast, shoots are negatively geotropic, that is, they will bend and grow upwards, or away, from the surface.
These geotropisms can be demonstrated easily with seedlings grown entirely in darkness. A seedling with its radicle (or seedling root) and shoot already in the expected orientation can be turned upside down, or placed on its side, while kept in darkness. The root will subsequently bend and grow downwards, and the shoot upwards. Because the plant is still in darkness, phototropism (a growth movement in response to light) can be eliminated as an explanation for these movements.
Several theories about the manner by which plants perceive gravity have been advanced, but none of them is entirely satisfactory. To account for the positive geotropism of roots, some researchers have proposed that under the influence of gravity, starch grains within the cells of the root fall towards the “bottom” of the cell. There they provide signals to the cell membrane, which are translated into growth responses. However, there have been many objections to this idea. It is likely that starch grains are in constant motion in the cytoplasm of living root cells, and only “sink” during the process of fixation of cells for microscopic examination. Roots can still be positively geotropic and lack starch grains in the appropriate cells.
A more promising hypothesis concerns the transport of auxin, a class of plant-growth regulating hormones. Experiments since 1929 have shown that auxin accumulates on the “down” side of both shoots and roots placed in a horizontal position in darkness. This gradient of auxin was believed to promote bending on that side in shoots, and to do the opposite in roots. Confirmation of the auxin gradient hypothesis came in the 1970s. When seeds are germinated in darkness in the presence of morphactin (an antagonist of the hormonal action of auxin), the resulting seedlings are disoriented—both the root and shoot grow in random directions. Auxin gradients are known to affect the expansion of plant cell walls, so these observations all support the idea that the transport of auxin mediates the bending effect that is an essential part of the directional response of growing plants to gravity.
And what an end to November and a start to the month it has been…
Firstly to those affected in any way by the adverse weather conditions…. my sincerest best wishes to you all, I hope it sorts itself out as soon as possible. To those who chose to stand up to the Green Party politicos [especially on RTE’s The frontline yesterday] more concerned with defending the amount of action groups who solve extreme weather conditions by sitting at a round table…. I applaud you. I also think Fionn has a point…
But thats another days work…. and on to Gardens we go…. well, as best as is feasably possible….
You see gardening is a funny business. It’s not a subject that one can put off. The elements maybe against the preferred conditions – but if [for example] the bulbs aren’t planted in the garden this December… it’s now spring 2011 before you will see them pop up… you follow? If you put it off last month…. you’d better get them wellies on or be a very fancy dancer – one that can dodge rain droplets 😉
Despite the weather, I’ve still been working out there. You heard me 😆 It has to be done.
first up is hedge cutting – some prefer to do it in the summer…. but if you have something like the forsythia which flowers on bare stems in and then goes into leaf – you’d be mad not to. Some say the best time is…blah blah blah 😉 I say, this when I’m doing my crataegus and my fagus. Its also when I’ve been cutting others escallonia… get the rakes, secateurs and the lopping shears out and go for it.
It is also a time for more select pruning. Maybe in this case the hedgecutters maybe a little too harsh. In this category I would add the removal of suckering growth – see the difference in leaves on the Corkscrew hazel [corylus avellana contorta – first image] ; the pruning back of smaller plants that have been let go a little – in this case the likes of the helichrysum [second image above – and similar in habit to lavender]; and also the pruning by hand saw of branches that have become a little elongated – almost tree like when it should appear as a shrub. Moreso, it is also to do with good garden hygiene.
But the biggest gig that most may possibly forget is the fact that it is tree planting season. The season when dormant and mostly native Irish trees get to go in the ground in their over wintering state. If you are looking for some ideas and names of, see this post on Irelands favourite native trees which can be planted now – I said now !!! Don’t forget the straps, buckles and tree stakes.
If you have existing trees – check the straps and buckles aren’t choking the trees – if they are – remove or loosen them.
Regarding your lawn…. you may get a cut in before the Christmas. Once again, the ye olde garden fraternity may suggest this is the wrong time – which is perfectly fine if it is the local croquet club… but if you are my Dad… well, you’ll be picking up the phone and telling asking me when am I getting my butt over to the house to cut that grass.
After that – the bird feeders still need filling, the shed needs to be painted and I’ll guess you never did the new-ish garden furniture last month ….well don’t say I didn’t tell you 🙄
If you take my advice – sure get it all sorted – then go and buy some instant colour in the form of winter planters, window boxes and hanging baskets. Really brighten the place up…. God knows you deserve it. Now all you need to do is to go and get that Christmas tree 😉
Whatever you do and if you are doing it yourself… stay warm, dry and be careful. If you are getting the gardeners [at least for me anyways…!] in…. put the kettle on and give ’em a nice cuppa and a mince pie. If ever I wondered what a kite must go through…. recently is the closest I’ve ever come to realising it 😆 Oh and in case I forget…. do enjoy 🙂
As a by the way…. just because its called peach leaf curl, it doesn’t mean it only affects peach trees. It will affect most Prunus related species.
Anyhow, I don’t like this one at all. It simply looks so ugly…. caused by the fungus Taphrina deformans [the second part of the name says it all…], it is spread by rain and wind where it will hibernate in stem cracks, scars or wounds and there is literally damn all one can do about it.
The leaves become distorted and bubble up like big ugly red blisters. En mass, it is pretty ugly to look at and I kind of feel sorry for the plant…. especially when all of the leaves fall off.
Whilst chemical control via any sort of fungicide will do the job… in my own garden I prefer to let nature do what it must and maybe from a biological control point of way I may get involved…. But the leaves do grow back and hopefully the plant will come good. But isn’t that what gardening is all about…
Can you imagine if every house in Ireland planted just one tree, how beautiful would this country look….
I really do love this time of year.
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