Germinating Citrus / Poncirus trifoliata

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Welcome to my new Blog. Today is an entry on germinating of the plant Citrus or Poncirus trifoliata.

I am actually trying to work on a new all singing and dancing butterfly website but for a number of reasons it will be several more months before this will be ready. I am looking at some really high tech things like Artificial Intelligence to build it and my time is limited at present and there is some information that I think should be on-line so I am writing it here.

The first thing to say is I am a bit of an inventor. I like to build my own gadgets and systems to do things cheaper and better. I have designed things like a room cooler made out of plastic lemonade bottles and a computer case fan held together with papier mache and cling film and a system to learn the grammar of Ancient Greek based on one devised to compose new music which is attributed to Mozart. This latter idea will be expanded and exploited as part of my AI system if I ever get my main site working.

If you want to breed lepidoptera you need the foodplants and citrus and related plants are very useful for a whole range of tropical swallowtails. I am also rather interested in citrus plants anyway. I have loved them since i planted some pips as a young child.

I obtained some seeds at around the beginning of December. This is the trifoliate orange and is hardy here in the UK. It is also deciduous unlike other citrus species so I will probably need to get some other Rutaceae plants which are evergreen for the occasional winter breeding.

The seeds were fresh which is important if they are to germinate. Indeed my supplier told me he took them out of the fruit in order to send them to me.

I then had a bit of a delay caused by my breaking the first aquarium heater and delays caused by Christmas post being slower. It was actually only on Christmas Day that I could plant the seeds. Aquarium heater? Yes that is right! I used my inventive skills to build a novel cheap propagator using an aquarium heater as the thermostatic control. It is all documented here

There is a lot of poor information on germinating Citrus trifoliata on line, which is why I am writing this. Many claim that it needs to be subjected to a period of cold to get it to germinate. It does not!  I was even told this by my supplier. I was thinking of testing various methods but this one is so reliable it would be a waste of time.

My research on-line showed this scientific paper which indicated that the thing to do was to plant the seeds in a propagator at 25 Celsius. This I did planting 60 seeds on the 25 December  By the 9th January just 15 days after I had some shoots showing and on the 14th January (yesterday) I had 37 small seedlings to transplant. This is a germination rate of just over 61% and of course there may be more to come later.

One important thing to note is that the seeds produce a very long root before a shoot and I had buried the seeds rather shallowly as the seed tray was not a deep one. This often meant that the seeds were pushed up out of the soil by those roots. You can see a picture on the link illustrating the design of the propagator above which will give you some idea.

Update 18th January. There are  now 50 seeds that have germinated which is just over 83%/

Update 22nd January There count is now 54 seeds germinated which is 90%. Just in case anyone is wondering there is no polyembryonism involved. Some kinds of  citrus produce more than one seeding per seed. One is a true seedling and the others are clones of the parent. This species is obviously not prone to doing this or at least the strain I have is like that.