Topic: who makes their own seed compost?

[nilly71]

What are the ratio's you use to make up your own seed compost?

Neil

[les65]

1 bag of mirical grow peat free and one bag (same size) of ji no1

[Eristic]

I use my own compost but the exact ratios would vary according to the raw ingredients being used. Soil, sand and even compost varies greatly.

Here's what I do. First I have a riddle with 1" mesh that is made to wheelbarrow size. Using this, step 1 is to pass topsoil through removing all large junk and weeds etc. This sifted soil is held in a large tub while the sifting process is repeated using the best garden compost. The soil and compost are then combined in the ratio 3 pots soil, 3 pots compost and 1 pot sharp sand added. The mixture is then stirred up.

This mix suits my needs but is easily modified. The mix could be further improved by passing through a smaller sieve but I rarely bother. Any odd sticks or small stones either get left in or hoicked out depending whether it is being used for seeds or potting up.

I do not add any fertilizer as there should be plenty of nutrients in the raw ingredients to get seedlings under way.When seedlings are repotted, they get individually fed according to their needs. Any large pots of compost from tomatoes, peppers etc are recycled back for the following year but used mainly for filling larger pots with strong plants.

Ultimately I think the potting compost will only be as good as the original garden compost from the Dalek or Moriati bag.

[nilly71]

Thanks for the replies ;)

Eristic
When you say top soil, can i  just use the soil from the allotment?

Neil

[Tee Gee]

Neil you initially asked;

What are the ratio's you use to make up.............. your own seed compost?

With all due respect to Eristics recipe I think his recipe (which is a good one ) describes 'potting compost' not seed compost as he mentions in his last paragraph;

Ultimately I think the potting compost will only be as good as

You ask;

When you say top soil, can i  just use the soil from the allotment?

I would say never to this for SEED compost! It is unlikely to be sterile!

I basically use the same procedure as Eristic  as seen here;http://www.thegardenersalmanac.co.uk/Data/Compost/Compost.htm

Do you agree Eristic?

Note; Click on pictures to enlarge!

[Eristic]

Tee Gee yes my mix is really potting compost but passing through the smaller sieve would convert it. Strictly, it should also be sterilzed but shop bought compost is rarely sterile either.

I use my mix for both sowing seeds and for potting on without any of the problems that seem prevelant in these forums. My seeds are all sown in 3" pots with seedlings transplanted either to individual 3" pots or shallow polystyrene boxes from the fish shop.

When you say top soil, can i  just use the soil from the allotment?

Yes. Providing it is of reasonable quality. It is the nature of your soil that determines the ratio of humus and sand to be added.

[Shirley]

A couple of years ago Gardeners' World has recipes for various compost mixes.
The seed compost was:

2 parts leave mould
1 part compost
1 part loam
1 part sharp sand

it didn't mention where you sourced the loam

[nilly71]

Thanks.

What is loam and humus?

Neil

[terrier]

For steralising seed compost, I'm told that small amounts can be done in a microwave cooker. Anyone try this?
Nilly71, I make my own loam by skimming of turf and stacking it (greenside down) until the grass has rotted down. As for humus, I think you could call compost humus but I'm sure someone will give us the official recipe :)

[tonybloke]

Definitions of humus on the Web:

    * partially decomposed organic matter; the organic component of soil
   
      wordnet.princeton.edu/perl/webwn

   

    * Humus (Latin - "soil ") is the organic material in soil lending it a dark brown or black colouration.
      en.wikipedia.org/wiki/Humus

    * A large group of natural organic compounds, found in the soil, formed from the chemical and biological decomposition of plant and animal residues ...
      en.wiktionary.org/wiki/humus

    * The dark organic material in soils, produced by the decomposition of soils. The matter that remains after the bulk of detritus has beenconsumed (leaves, roots). ...
      www.bioquaticsupply.com/html/glossarybug.html

    * A dark colored, stable form of organic matter that remains after most of plant or animal residues have decomposed.
      www1.umn.edu/webdd/resources/glossary.html

    * The brown or black organic part of the soil resulting from the partial decay of leaves and other matter.
      www.thegardenhelper.com/dictionary.html

    * highly decomposed plant and animal residue that is a part of soil
      www.jefferson.k12.ky.us/departments/EnvironmentalEd/blackacre/glossary.html

[terrier]

 ;D  All sounds like good composted material to me..  'The wonder of Wiki'.

[Eristic]

I would just like to question the issue of sterilized compost. For general allotment flower and vegetable growing sterilized compost is not required at all. Waste of money. How can I say that? You ask! The sterile compost is only required when conducting scientific studies, and is desireable when sowing exceptionally rare or expensive seed. Typical veg seeds have evolved to expect a hostile environment and are all well able to cope with the typical fungal spores in the soil. Larger threats to early life such as woodlice and slugs/snails will take up residence regardless of the compost used.

Most germination troubles are either caused by poor seed or an impatient gardener sowing too soon and too wet.

[nilly71]

Thank you for the info.

I bought some sharp sand today and have some compost on the allotment made up of well rotted horse manure, mushroom compost and general household shredded paper/card.
Do you think this will be ok?
I don't have any loam and only got the leaves about a month ago, so they won't be ready until next year. I do have mushroom compost left over if this would be better off used with th sharp sand.

Also, do i add potting compost to the base of the pot and a seed mix for the top. I have loads of clearing of the plot to do and this year might not have the time to start them off in a seed mix then re-potting them to a potting mix.

Neil

[Eristic]

I would be wary of the manure if using the compost for seed sowing. There should be more than adequate feed already in the soil to keep a seedling going for a few weeks. As for the loam, hardly anybody has true loam any more due to space and time restrictions. Try using the mushroom compost and soil with the sand. Mix a small amount to see what you get. Aim for a gritty crumbly mix.

As for filling the pot for seeds. You do not want a deep pot for sowing seeds. If you use 3" flowerpots and sprinkle 20-30 seeds on top, give a quick stir and a dribble more compost. Job done. Once the germinated plants start producing the second set of leaves it is time to move them on to bigger quarters.

[nilly71]

Thanks for the advice.

Does the info work the same way if i was to use rootrainers or does the seed go straight into them?

Neil

[growmore]

Not being controversial but I would never use topsoil in a mix for seed compost .
I want to know that what I am pricking out are the plants which I have sown the seeds of. Surely there's bound to be weed seeds in top soil or garden soil .
Also you might just get some soil from the garden where you had a bit of  clubroot, the seedlings may not show any pronounced affect of it, but the plants as they mature will, wherever they have grown you will have the disease in the soil for a few years .. I use bought general purpose compost for most of my veg seed sowing. Sieving it if necessary... Same stuff for potting on but with a  bit of  sharp grit mixed in for drainage. 

[Eristic]

I want to know that what I am pricking out are the plants which I have sown the seeds of.

This is a very fair comment and it is true that there will be some weed seed germinating. Get used to it. There will always be weeds and the sooner a gardener gets to know and identify the weed from the crop plant the better. I did rather assume that anyone wanting to make their own sowing/potting compost could tell a hoary bittercress from a cabbage or tomato.

Regarding the soil bourne diseases, that too is a valid point but is really panic for the sake of panicking. Anyone who is easily paniced should pay up and look big buying from the shops but in reality keeping a tightly controlled closed loop does much more to prevent/contain disease than anything else.

Incidently, I've found that the weeds tend to be much slower to germinate than the veg seeds. Most of the weed seed comes from the compost heap rather than the soil content.

[kt.]

What are the ratio's you use to make up your own seed compost?

I do not use homemade compost for starting seedlings.  100% multipurpose PB compost purchased from the lottie shop ;D ;D

[terrier]

I have some very industrious moles in my garden that kindly leave large mounds of potting soil all over my lawn  >:(

[markyb23]

I don't really make my own seed compost, but, i just use a fairly fine peat based multi-purpose compost and then add loam based seed or John Innes No 1 compost until i get the texture that feels about right. Maybe put some sand in too if i've got some.
 I find that multi-purpose comp on its own can get a bit too wet.
 Whenever i get the chance i try and get a load of the compost and other bits and peices from Gordon Riggs garden centre. Their stuff always seems good quality and very reasonably priced.