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Seed Sowing Experiments

Seed Sowing Experiments

I started sowing seeds in 2006 and gradually became hooked. I tried sowing in bags after reading an HPS article some time afterwards that involved leaving the bags outside but it did not work for me. In the 2012 Autumn Cornucopia there was an article by Ann and Bob Armstrong on the same subject which I decided to try myself this year. My sister had died early last year and so seeds received from the RHS and HPS were virtually untouched and I now had yet more from the same sources this year, as well as seeds left over from years ago, about 200 packets altogether. I wanted very much to give them all a chance to germinate using Ann & Bob’s experience. A comparison of the methods used is below.


Both involved pre-labelled and dated re-sealable sandwich bags.

  Ann & Bob Armstrong’s Experience Mine, as amended for practical purposes
Bag contents Gritty mix of perlite and B&Q paving sand, adding seeds and water to the bags with a plant sprayer. 50:50 approximate mix of perlite and horticultural sand added to a large bowl and mixed with enough water to dampen the whole. 1 tablespoon of the mix added to a bag for tiny seeds, 2 for larger seeds and 3 for the very large. Seeds added and bags shaken and contents spread out inside.
Where placed Bags placed in a transparent storage box In a cool light room. On every window ledge in the house from mid April. Back windows for seeds needing temperatures 20C and above, front windows for cooler needs
Germinations Easy to spot. Gently slid onto pot of seed compost, topped off with very fine grit, stood in bowl of water for a few hours. After a few days the tiny seedlings righted themselves and grew happily. Easy to spot. A bag was gently emptied into a bowl of water at room temperature or, where seedlings were large, they were sometimes gently extracted individually before being potted on


The success rate was much higher than I expected, probably as high as Ann & Bob’s. Brassicas, peas and lettuce were particularly successful, the first two often having well developed and enormous roots. Germinations were far quicker than I anticipated – 6 days being Ann and Bobs record and mine being 5 for mizuna. Germinations included 2007 seeds as well as many in more recent years up to 2012. Some germinations were from seeds that I had tried to grow unsuccessfully in more conventional ways before. Annuals, perennials, trees and bushes germinated.

About 50% of exceedingly tiny seedlings did not survive and, in some cases, none survived at all. This was probably because they were extremely difficult to handle without damaging them. When I try again I will therefore try to keep closer to Ann & Bob’s method where there seems to be less handling. I also found that I lost seedlings if they were de-bagged whilst their leaves were still only half out of their seed case.

Using sandwich bags and emptying them in water usually meant that none of the root system was broken off, which can be the case taking seedlings from bags individually or pricking them out from compost. Intertwined seedlings in water can fairly easily be separated, if carefully done. This was the case with at least 50 germinated sunflowers, all intertwined, from 1 bag!

Where germinations were unsuccessful, I emptied the bags in the garden, on the surface of a pot already planted up or just mixed the contents with ready prepared compost for seedlings. I have always done the latter with compost used for unsuccessful sowings and subsequently had pleasant surprises when an unrecognisable stranger pops up.

Stefanie Bowman

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