Monday, 19 November 2012

The Rubus Experiments, pt 1

Note to secondary and FE biology teachers: feel free to use this as an example of a simple and practical botanical experiment.  The link presently comes up second on the first page of Google when searching for "The Rubus Experiments".  The Rubus tab across the top of the page will link to the site where I'm posting the experiments progress.  

  The ramp out front needs replacing as it is presently bridging the damp course.  Everyone finally admits it, so that'll likely happen a few months from now.  The ramp covers more than half the surface area of the front garden, so it'll mean something of a slash-and-burn of plantlife out there.  That Buddleia will go (TFFT!) but so will my brambles.  Those brambles have been there for over ten years and they're a brilliantly heavy cropper.  Every year in late Summer/early Autumn we have more blackberries than we know what to do with.  I didn't plant the bramble myself and nobody knows how many generations of Rubus have grown here.

  More important than sentiment is genetics.  Genes are like stories: they shift in the retelling.  The verses which suit the culture tend to be retained, to grow and to flourish, whilst those which don't will fade into obscurity.  That plant has a genetic heritage which enables it to hold its' own in that place, that soil, those conditions, in spite of competition from other plants.  That plant belongs to that garden, and a similar bramble bought from the garden centre might not suit the space in the same way.

  What to do, then?  Well, I intend to keep the bramble one way or another, but if the bulk of it must be chopped down then I might as well try some stuff out.  I'm not saying this'll work, so you shouldn't take this as a guide to action.  Still, here's what I'm getting up to:

The tools I'll need.  
I've filled the pots with soil from my garden, the same soil the parent plant is growing in.  Most would say to use potting compost, and I'd tend to agree.  My soil is crumbly, silty loam which successive gardeners since the 1930s have dug endless peaty compost into.  If I wanted a better medium for growing I'd have to invent it.

I took the soil from the beds.  Specifically from a point furthest from where my V. faba are growing.  No sense in depriving the beans at this time of year.  Once filled, I took cuttings from shooting tips of the Rubus. They're easily spotted by the claw-like, mitroid tips.  These are where new growth is happening most vigorously, so they should be most likely to take root.  The greenest shoots are best.  Prior to cutting the blades of the scissors were suspended in a pan of water as it boiled.
The growing end of a vine.  
The shoot cutting, size 7 hand for scale.  

I took only healthy shoots, avoiding any that had a problem with greenfly.  Heh, "problem", kinda makes it sound like "if you're not talking to your plants about greenfly..."  Aaanyways; once a shoot cutting was taken, it had to be rinsed under the tap.  A good soaking helps prepare the cuttings.  A hole was made in the centre of my potted soil using a skewer and the cut end put into the soil.  I then used my thumbs to press the soil down gently, just enough to close the hole without compressing the soil.  

I've made five of these - each of roughly the same length - and put them in the Nursery.  Mike has been relocated to my bedroom windowsill for the duration.  Mike seems to be recovering well from his infection.  Once there they each got a solution of 4:2:6 up to the yellow line on the saucer.  Now for the experiments.  I say experiment, but these are more akin to case studies than true lab experiments, albeit with certain controls in place.  

  1. I've taken four cuttings of thin, green shoots.  One of a thicker, purpling shoot.  Which will fare better?
  2. Two of my shoots curve.  I've pointed the tips of these away from the Sun, where normally plants bend toward the Sun.  Will the phototropic action of auxins cause the whole shoot to straighten up as it brings itself sunward or will the tip kink towards the Sun instead?  

Basic exercises in botanical study, but interesting for all that.  I'll observe the cuttings over the coming months and report on their progress.  Here's the five as they stand today:


  1. I just noticed your label "I wonder what'll happen if..." - best sort of science, that is! Looking forward to following the experiment's progress.

    1. Same here. Just so long as I end up with one viable plant at the end of it I'll be happy. My money's on Milo.

      I've moved the whole experiment over to a new blog. That way I can keep this one about the garden without monotonous progress reports. New blog's at:

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