[Sparkyweb]

Hi all,

First proper post!
As mentioned in the intro thread like many others I had a little more time on my hands last year and spent it in the garden! I had pretty good success.
I have been using the winter months for research and planning and my thoughts have gone onto the practical side of planting.... last year I just used whatever compost I could find (and I think things were ok). This year I知 looking at the wide varieties and just getting confused.
Do I need all of the different varieties?
There can be a lot of prices differences - does it make a difference?
Should I use seed compost and then pot out into no1 type etc.

So many questions!
Mark

[AndyRVTR]

Compost is only a growing medium, some have food to last a few months, some have none. Personally I like to sow seeds in either purpose made seed compost, or sieved multi purpose compost, neither with feed as they don't need it at sowing stage. Then I tend to pot on into standard multi purpose compost before planting out, or into compost with feed, depending on the plant. Once plants are in their final growing positions, I will feed them throughout the season with either manure pellets, fish, blood and bone, growmore or one of the Chempak range, again depending on the plants.

[mumofstig]

I avoid commercial compost that has any 'green waste' in it, because I had a batch one year, that nothing grew well in (if at all.) It was widely reported that green waste, collected by Councils from peoples gardens and sold to the compost producers, could contain residues from a weed-killer used on lawns, which was causing the problems.
Personally I use multi-purpose for everything, just sieving it for the smaller seeds, and like Andy, feed plants as required, I tend to use a liquid feed, which works well for me.

[hasbeans]

If you can avoid dependancy on peat based compost you're doing the planet a favour.  There is no such thing as sustainable peat despite what the blurb on the packaging says.   

[Growing Weather]

The problem I have with using most bagged peat free compost for sowing is the mould growth on the surface due to the producers not properly composting the material. I was able to buy a very good universal bagged compost but since moving I can't lay my hands on it so am currently in the process of trying out a few different types. So far I have Levington in pole position with Sinclairs (because of the price) I paid in second place.

[mumofstig]

If you can avoid dependancy on peat based compost you're doing the planet a favour.  There is no such thing as sustainable peat despite what the blurb on the packaging says.   

What about the Moorland Gold ones that use peat collected through water filtration sold by Organic Gardening?
https://www.organiccatalogue.com/products/moorland-gold-compost_mh5974

[hasbeans]

If you can avoid dependancy on peat based compost you're doing the planet a favour.  There is no such thing as sustainable peat despite what the blurb on the packaging says.   

What about the Moorland Gold ones that use peat collected through water filtration sold by Organic Gardening?
https://www.organiccatalogue.com/products/moorland-gold-compost_mh5974

OK...I guess an exception to the the rule in that it is dredged from lakes and resevoirs but let's be honest, it's availability only muddies the waters on the peat use debate   

The Horticultural sector would develop even more alternatives if peat was banned rather than the so-called ban being 'voluntary' as it currently is.  The lack of a ban means many commercial growers are still using unsustainable quantities of mined peat and amateur growers are not being encouraged enough to buy alternatives .  I imagine Moorland Gold is already unaffordable to most and would only become more expensive if it was the only peat product on the market via a loophole to a total peat ban.

[Potty Plotty Lotty]

In recent years I've started buying a "branded" multipurpose compost to start seeds off with and then used a cheaper multipurpose compost (Verve/Wickes mainly) for potting on etc with regular feeds.

The main reason for this is that there were increasingly reports about the varying quality of the generic brands and although I hadn't experienced this myself I didn't want to take the risk.

I tend to go for Jack's magic initially (peat based I'm afraid) which I prefer to the Clover that I bought last year (a few hours before lockdown was announced!). Got a bag and a half in the garage at the moment...

I'm considering trialing some New horizon peat free compost as this came up very well in the Which? trials last year.
 

[bobbyt]

I'm using coco coir blocks this year as a trial instead of seed compost and MPC. Found some on line that grow to 9 litres at ｣3.50 each. Bit more pricey I suppose, but it is peat free, and uses a waste product, mix with some FBB for feed, and vermiculite for water retention too. I'll let you know how it goes.

[Sparkyweb]

Great, thanks for the advice.
I think I知 going to stick with the seed compost I致e brought to start and then revert back to multi purpose when I pot them out. Would some vermiculite assist the potting part?

[jezza]

Hello not saying alot about compost but be careful with any peat free compost I drove past a pile of alternative  compost as mentioned on this site it absolutely stinks,its garden waste and human sewage sludge mixed with chopped straw and composted for 9 months    jezza

[rowlandwells]

I'm afraid I'm not  convinced to using  peat free compost  we found clover peat based is one the best buys we haven't had any problems with this brand

as I have  said  before if the compost manufacturers get there act together to produce a decent peat free compost I would be the first to change to peat free and it needs to be at a comparative price like the peat based

you see i can't see me changing to something that doesn't work for me spending hours in the greenhouse potting on or seeding its just not worth the risk of changing from something i know works to something I'm not sure of?

there's also the argument that home gardener should be banned from using  peat compost when
commercial growers can use peat based as much as they want i sometimes think those bods at [Defra] make it as the go along what's the difference between the home gardener using peat based to the commercial grower using it  when the home gardener uses a lot less that the commercial grower its just a crazy situation 

there's quite a rite up in which gardening Feb issue well worth reading and i have to say i will continue using peat based until its banned and that means all not the chosen few

[Plot 1 Problems]

Meanwhile I happily use cheapo multipurpose compost from my local supermarket on the three 70l bags for a tenner offer. I use it for seed sowing, potting on, everything! To contrast others, The green waste compost we get here from our local authority has been reliably fantastic as a soil conditioner, though as others have said it does stink initially.

[hasbeans]

Great, thanks for the advice.
I think I知 going to stick with the seed compost I致e brought to start and then revert back to multi purpose when I pot them out. Would some vermiculite assist the potting part?

Perlite or grit mixed in the compost, vermiculite on top of the seeds is how I do it.  Like Plot 1, I only use the cheapo multi purpose compost, mostly because I grow a lot of stuff in big pots and try to keep costs down by using the same compost for everything.  I found vermiculite mixed in kept the pots too wet and seemed to discourage root growth.

[Fishplate42]

...This year I知 looking at the wide varieties and just getting confused.
Do I need all of the different varieties?
There can be a lot of prices differences - does it make a difference?
Should I use seed compost and then pot out into no1 type etc.

So many questions!
Mark

Hi Mark,

As has already been mentioned, commercially produced compost is just used as a growing medium. Some use it to fill entire beds or mix it with the existing soil to use it as a soil conditioner, but its main use is for sowing seed and potting on.

Now, being an old fud who has been doing this for well over forty years, I remember the days when the choice was not so overwhelming. All the books and magazines talked about John Innis composts and the odd mention of the newfangled (to me at the time) multi-purpose compost.

My view of them was somewhat skewed by the fact that the multi-purpose compost of the day had no soil in it and was almost 100% peat with some "added nutrients". I could never find out exactly what those nutrients were (are?) as there was no mention of exactly what quantities have been added. It would also be very hard to re-wet if it dried out. It does not seem to be any different today. I suspect that batches vary, even from the same producers. What I do know is that it usually produces good fast growth for the first few weeks, and then it is up to the grower to top up the nutrients as the plant requires, usually by adding liquid feed. Nothing wrong with all that, but you do need to be aware of what nutrients the plants need and more importantly; how much to apply and at what interval. You can of course just keep repotting into new compost as your plants grow, but you are repotting into compost that contains the same level of nutrient as the seed was sown in. Nothing wrong with that, as long as it works for you.

John Innis is actually a formula, not a brand name. It is a staged growing programme that takes plants from seed to mature plant by increasing the amount of nutrient in each potting on mix. The base soil mix is also formulated to keep everything constant.

JI seed compost is just the base mix with added phosphate to promote root growth once the seed has germinated.

JI No.1 is the base mix plus one measure of the nutrient mix.   

JI No.2 is the base mix plus two measures of the nutrient mix.

JI No.3 is the base mix plus three measures of the nutrient mix.

The formula is readily available on the internet, but the simplest explanation I can find is here: https://www.rhs.org.uk/advice/profile?pid=952

I hope this helps,
Ralph.