Friday, 28 October 2016

pruning and potting

At the start of today I thought I would have finished putting the pots in the greenhouse by dusk. Hope springs eternal.  Endless over-optimism is something of a gardener's trait, otherwise you wouldn't bother.  One of the ladies from Tynings Climbers told us that when they bought one of their tunnels she said it would take a couple of days to put up: it took six weeks.

I have re-potted two of the agapanthus.  They came out of their pots much more easily than I feared they would, with only a little help from the bread knife.  The trick (or at least the way I get things out if they won't lift out of their pots) is to upend the pot and tap the rim sharply on the edge of the greenhouse bench, directly over a leg otherwise all that happens is that the staging vibrates. You need to have your hands positioned so that you can feel the moment the root ball starts to come loose, at which point you swing the pot back to the horizontal while finding a spare finger to break the fall of whatever is in the pot, otherwise your precious plant will land on its head and snap bits off itself.  The agapanthus pots were about at the limit of what I could manage using this method, one being thirty-eight centimetres in diameter and the other slightly larger.  I had held back on watering recently because I knew I was going to need to lift them, but even so.

Agapanthus grown in containers will need periodic re-potting, since they will grow inexorably until the pot is absolutely stuffed with their thick white roots, gradually raising themselves up during the process until there is no gap left at the top for watering.  The books say they flower better if pot bound, but I've found that once they are too crowded in their pot, and perpetually slightly short of water because you can't get it to soak in, they give up on flowering.  These two, which were huge healthy looking specimens that would have sold for north of thirty pounds each in a garden centre, managed the grand total of four flower stems between them this year.  Having learnt from previous experience both were growing in machine made, smooth sided, large versions of the traditional flower pot, to make sliding them out when the time came as easy as it could be.  If you are planning to grow agapanthus in a container I would steer clear of anything rustic and hand made with a rough internal finish or the roots will stick to it, and don't for goodness sake choose a pot that's smaller across the top than it is further down.

I thought that if I sliced the bottom two inches off the root ball of the first plant it might fit back in its original pot with a gap at the top for watering, but it wouldn't, and after messing around trying to reduce the root ball enough to go in I gave up on that idea.  It needed a bigger pot, but searching through the pot shed I didn't have to, and I decided I was going to have to bite the bullet and divide it.  The bread knife went through the outer white roots almost as easily as cutting bread, but when it got to the core of the plant it was another story, and I had to resort to a pruning saw. One of the joys of having a new pruning saw for pruning is that I can use the old one for jobs like dividing root balls.

Unfortunately nasty grating noises and a feeling of resistance as I sawed warned me that there was something solid embedded in the compost.  I wondered if I had left an old crock inside when re-potting previously.  I once spent an unbelievable amount of time diligently sawing away with a very blunt saw at a bamboo I'd been told to divide at the plant centre, only to find out when the root mass finally fell into two halves that the reason why it had taken so long and been such hard work was that I'd sawed right through a piece of terracotta.  I went to fetch my spade, to bring some leverage to bear on the agpanthus problem, and remembered to angle the whole operation so that if the root ball suddenly gave I wouldn't crash the handle of the spade through the side of the greenhouse.  When eventually the agapanthus yielded, by now rather battered, three irregular lumpy stones fell out of the middle of the compost.  I have no idea how or when they got there, but the moral of the story is to try to keep container grown plants free of such rubbish, in case you ever need to divide them.

Neither of the two halves of the original root ball wanted to fit back into their old pot without further surgery, and by now I was getting fed up with chopping more and more roots off a perfectly healthy plant.  I managed to find a couple of old black plastic pots that will do for the winter, and can decide whether to buy more large terracotta pots in the spring.  Given how much large clay pots weigh and that black is a recessive colour I might be able to get away with using the plastic pots at the back of a display.  Or perhaps I am in danger of ending up with more agapanthus than I need and should give one of them to the garden club plant stall next year.

After that the plant from the thirty-eight centimetre pot was able to go into the bigger agapanthus pot, once I'd sliced a disc off the bottom of the root ball.  Two down, two to go, although one will be easy to get out of its present container because the pot has split.

I brought in two of the large fuchsias as well, and cut them back fairly hard as the specialist fuchsia websites advise, and then went over them painstakingly cutting the leaves off, since the experts recommend storing them leaf free.  I didn't insist on taking off all the smallest, newest leaves, but the larger ones went into the compost bucket, together with the soft shoot tips.  It feels brutal and counter-intuitive to attack a plant in such a way that ten minutes previously was looking perfectly healthy and happy, but the aim is to avoid botrytis and other fungal rots.  I did the same thing last year and it worked.  The plant centre manager used to delay putting the stock of fuchsias under cover for the winter until they had dropped their leaves naturally, to avoid having the fallen leaves mouldering in the polytunnel, but some of my fuchsias are not hardy and I need to get on with filling the greenhouse and can't start leaving gaps for things to come in later.

The Plectranthus argenteus I'm overwintering had a drastic haircut as well.  It seemed a terrible waste to throw away the material for so many potential cuttings, but I don't need any more plants. My plants came from seed and I haven't tried taking cuttings of this species, but it has the vibe of something that would root really easily.  Some of the stems seemed half way to throwing out roots in mid air.

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