Seed Success in the garden Week 13

Seed Success in the garden Week 13

Seed Success in the garden Week 13
A few weeks ago I shared my seed sowing ideas with friendsI mentioned the tests and comparisons I was making to find the most successful way to sow seeds and grow on seedlings.

These have now to conclusions, and the answers are not what might have been expected.

Test one was on sweet peas. With a historic 50 per cent germination rate I thought there had to be ways to improve production. Thompson and Morgan have a  useful page of suggestions, but some of it seemed just too much hassle.  So I put it to the test.

They included soaking in water, soaking in tea – using the tanins to mimic passing through a birds digestive system. And also chipping the seed, not chipping them, planting them shallower or deeper than suggested.

Seed success with sweet peas
Seed sowing test with sweet peas

Nothing made a real difference, except for the deeper planted seed. They had not been soaked or scored in any way, just planted 4cm deep as opposed to 2cm. They came up faster and notably stronger.

I shall repeat that specific test for confirmation this week.

The other test was on the sowing medium, specific John Innes mix seed compost or a vastly cheaper multi purpose. I use the B&Q Verve compost, and recommend it highly. For most purposes I mix the MP compost with some sharp sand at 4:1

Seed success with multipurpose compost

I sowed 5 different seeds – Digitalis, Achillea Cerise Queen, Achillea Gold Plate, my own super Delphinium strain and some chilli peppers left from an earlier sowing – in lines across trays of compost.They were lightly covered with compost and soaked them from below in a water tray. They were next to each other in a heated propagator.

This produced interesting results in what actually germinated and how they behaved in the weeks following.

In the JI seed compost the Digitalis was up first after about a week, followed by the Delphiniums and a few of the Gold Plate. Nothing was going on with the MP still.

Another few days later and there was growth in all 5 lines of the MP tray, but nothing different in the JI.

A further week passed and all was ell with the MP, but the Digitalis had all died back in the JI tray.  My conclusion was that the composts were drying out at different rates, and the MP retained water longer. The Achillea Gold Plate and Delphiniums were all pricked out into trays and look strong. I have left the MP tray still to watch the slower growing chilli seeds, and to see what happens with the faster growing Digitalis.

Testing different sizes

The final test was in potting on, and what happens when using larger or smaller cells for growing on. I used 24, 54 and 60 cell trays available from the garden centre.

Delphinium seedlings
delphiniums in 60 cells.
Delphinium seedlings
Delphinium in 24, 54 and 60 cell trays

After 3 weeks the 24 cells plants are showing strong growth and ready to pot on further. The 60 and 54 cell plants are not so evidently growing away. They are are susceptible to  some cells being either too wet or too dry.  And it is hard to tell if the seedlings are not growing in the smaller cells, or if they are being restricted by them.

I will take them all apart this week for a definitive answer, even though that may mean sacrificing some of them.

So the conclusion is to use larger cell trays and stick with multipurpose compost, rather than the more expensive John Innes seed  mix.

 

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