All is not well in the garden. . . . .
At first glance my long border is looking quite beautiful at the moment (sorry not very modest of me!) but look closer and a nasty problem is revealed. . . .
The problem is with a beautiful lupin that has graced my garden for several years now with its wonderful blue and white spires. This lupin is under attack and I am waging war on its behalf. The attackers appear to be Acyrthosiphon pisum, more commonly known as the pea aphid. Now I don’t even know how to pronounce their name and they seem to be rather clever little bs, but I am trying to beat them at their own game.
Firstly I tried the standard soapy water treatment, but instead of a gentle spray I resorted to practically giving my lupin a bubble bath, stem by stem. I also removed the worst affected new stems and disposed of them. I am not sure who ended up the wettest, me or the lupin, but I was hopeful I had got the infestation under control. Not so! The next day there were still plenty of the creatures about. This time I noticed something quite clever – every time I touched a stem the aphids would just drop to the ground. Pretty good defensive tactics on behalf of young Pisum! However, I refuse to be beaten by something only a millimeter long so I devised new tactics myself. I started cupping my hand under a stem and just tapping it gently – the aphids then obligingly dropped into my hand. . . .wicked laughter here.
I then became obsessed – 2 or 3 times a day I would go and send more of these aphids packing trying to work out whether I could kill them quicker than they were breeding. I think we are about breaking even at the moment.
I did a bit of research:
Mature pea aphids live for about 30 days and give birth to up to 12 nymphs a day. Each of those takes 7 to 10 days to reach maturity and start producing more nymphs. Do I stand a chance? I think not! What is more, overcrowding or poor food triggers the production of winged individuals in subsequent generations who just fly off and find another plant to destroy! Usually adults reproduce by viviparous parthenogenesis which basically means ‘no males required thank you very much’, but as the days get shorter and colder sexual aphids are produced which then mate and produce eggs. These eggs area able to survive the winter and new aphids emerge in the spring to start all over again.
Isn’t that interesting? Does it explain why this is the first year I have been bothered by these aphids? Not really, but maybe the warmer spring has allowed more of them to mature successfully.
All sorts of research has been done on this freefall survival strategy of some aphids: what age do the aphids have to be before they know how to drop?, how long does it take them to locate and climb back up the host plant?, can they find the host plant again if they are blindfolded? (Not really, but they did try them in the dark!) All very interesting I am sure if you are interested in that sort of thing, but I would much prefer research that helped me to get rid of them without killing bees at the same time.
I would be quite happy to just keep them under control while the lupin flowered but we are going away shortly for ten days. Should I sacrifice my beautiful lupin to protect the rest of the garden or can I assume the bugs will stay put on the one plant until I get back. Hmmm, a difficult decision. Watch this space.
But rest assured, if any of them dare to hatch next spring before the bees are up and about it will be chemical warfare in Aberdeen!
Next Garden Update: Lilac, lavender or just plain purple?