Growing from Seed-Floatation

Lee Poulsen
Wed, 20 Nov 2002 23:50:45 PST
Mary Sue,

Thanks for re-posting my previous post on the flotation method. The reason I hadn't posted yet, was that I was looking for my copy of that post since I didn't want to re-type all of that again.

I never did answer why I wait until a leaf forms (or Jim Shield's question about Cyrtanthus that never send out a green leaf shoot). The reason I wait is because, from trial and error, I've found that when I planted seeds that had a root, but no leaf, I would sometimes lose half or more of them, and no leaf ever germinated. In one case (I can't remember which species), about half the floated seeds had sent out a leaf and half hadn't, but all the seeds had a decent root of about the same length on them. I planted them all in one pot and the seeds that hadn't sent out a shoot, never did send out a leaf and disappeared. The ones that had sent out a leaflet all grew and eventually became full-sized plants. So maybe it's superstition on my part.

As for some of the Cyrtanthus species, of all the Cyrt. species I've tried so far, all have germinated for me using the flotation method. However, some of them resulted in none of the seedlings sending out a leaflet. I kept waiting and waiting, expecting the roots to mold and eventually die, or the seedling to stop floating, sink, and eventually die. Instead, for these few types, a small bulblet would form right below the surface of the water and proceed to grow larger--and continue floating. I eventually decided to plant the little bulblets that looked just like small offsets. These eventually sprouted leaves and proceeded to grow normally after some time. Sorry, but I didn't keep a record of which species did this nor how long or during which season they eventually sprouted.

A couple of other points to mention (since I've been recently sowing and floating seeds since, most of the seed I try is mediterranean climate stuff and typically germinates in the autumn in their native habitat--which, as Mary Sue pointed out, it now is in California)
1. I monitor the seeds daily in case one or more of the seeds that are bad somehow, and won't ever germinate, start to grow mold or fungus. Some of these funguses spread rapidly even to healthy seed and kill them. I remove and throw away any seed that shows any kind of growth (other than a root) as soon as I see it appear.
2. Some seed is so slow germinating that the water starts to get dirty looking or grow algae and turn green. In these cases, I carefully pour out all the water and add brand new fresh water from the tap to replace it at regular intervals. Or if I'm particularly worried or it's particularly rare, I prepare a new clean cup with water and re-float the seeds in the new cup. I usually give up after a couple of months since then it seems that the seed is too old or dead or something is otherwise wrong with the seed. Is two months not long enough or too long?

Anyway, I'm no expert, but do it this way merely based on the experiences I've had trying to get papery/winged seed to germinate.

--Lee Poulsen
PBS Treasurer
Pasadena area, California, USDA 9-10

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