'Which?' - Best composts 2013

[Anonymiss]

Best compost for raising plants

J Arthur Bower’s Seed & Cutting Compost
Test score: 91%
Peat content: 95%
Price per litre: 20p (for a 20-litre bag)

Sold specifically for seeds and cuttings, this compost just pipped our other Best Buy to the post for seed sowing. It has a nice fine texture, too, making it less likely that you’ll bury tiny seeds too deeply. The young antirrhinum plants potted into this also thrived - as did our tomato seedlings, although some had paler leaves than those grown in our other Best Buys. As with most brands of composts, bigger bags work out cheaper per litre. The 35-litre one costs about £4.49 (13p per litre) and the 50-litre bag is even better value at £5.99 (12p per litre).

Verve Grow Your Own Growing Bag
Test score: 91%
Peat content: 55%
Price per litre: 7p (for a 27-litre growing bag)

While not intended for seed sowing, both seeds and seedlings thrived in this growing-bag compost, exclusive to B&Q (Verve is a B&Q own label). It's the cheapest of our Best Buys by some margin - especially if you opt for the 'five bags for the price of four' deal. The compost in our bags contained a few largish pieces of wood that needed picking out before sowing seeds in it, but this was only a minor inconvenience. When buying, be sure to steer clear of the peat-free version (Verve Grow Your Own Peat Free Growing Bag) as neither seeds nor seedlings thrived in this.

Verve Sowing & Cutting Compost
Test score: 89%
Peat content: 75%
Price per litre: 31p (for a 12-litre bag)

Despite being sold specifically for seeds and cuttings, the seedlings we potted into this B&Q-own-label compost thrived, too. In fact, there were signs it was a little too nutrient-rich for seeds preferring meager rations, because while our basil germinated and developed well, the leaves of a few of the seedlings looked slightly scorched. This compost has a light, fluffy texture that makes it pleasant to handle and ours had no coarse pieces likely to bury tiny seeds too deeply. However, it is considerably more expensive per litre than our other Best Buys, partly because its only available in 12-litre bags. New for 2013 are 50-litre bags too but we can't recommend these because compost is a different formulation to that in the Best Buy 12-litre bags and we have not yet tested it.

Verve Multipurpose Compost
Test score: 88%
Peat content: 58%
Price per litre: 15p per litre (for a 20-litre bag)

B&Q’s own-label multipurpose may be our lowest-scoring Best Buy, but we think you’ll still be pretty chuffed with plants you raise in it. Both seeds and seedlings did well in this, though on careful inspection there were signs it was a bit too nutrient-rich for our two ‘sensitive’ species. The leaves of some of our basil seedlings looked a little scorched and there was slight mottling on some of our antirrhinums, but nothing they wouldn’t grow out of. This compost has a light, easy-to-use texture. Larger bags are better value: the 60-litre bag costs £4.98 (8p per litre) and the 125-litre bag £6.98 (6p per litre).


Best compost for container plants

Levington Multipurpose Compost
Test score: 88%
Peat content: 40-70%
Price per litre: 11p (50-litre bag)

This widely available peat-based compost has a nice light, fluffy texture. As well as peat, it contains wood fibre, composted bark and green (garden) waste. Our pelargoniums looked magnificent in August during an all-too-brief dry, sunny spell, but ran out of steam a little sooner than those grown in our other Best Buys. In all three of our Best Buy composts, our potato crop was impressive and the tubers were top quality.

Miracle-Gro All Purpose Enriched Compost
Test Score: 88%
Peat content: 40-70%
Price per litre: 10p (50-litre bag)

Made by the same company as our Levington Best Buy, this compost contains wood fibre and coir as well as peat, so is a very different mix. However, it’s equally pleasant to handle and our plants grew much the same in both. By October, as you’d expect, none of the pelargoniums looked brilliant, but those grown in this Best Buy compost looked marginally more vigorous than the ones in the Levington compost.

Verve Grow Your Own Peat Free Growing bag
Test score: 88%
Peat content: 0%
Price per litre: 7p (27-litre growing bag)

The cheapest of our Best Buys by some margin. Exclusive to B&Q (Verve is a B&Q own label), this peat-free compost is made from bark, wood fibre and composted green (garden) waste. It’s a bit coarse to handle and ours included a few largish twigs – a minor niggle, as our plants certainly didn’t mind. Sold as a growing bag, there’s little risk of straining yourself when carrying bags of this around as they only contain 27 litres of compost.


Full test results

Composts for raising young plants
http://img38.imageshack.us/img38/8823/composts1.png

Compost for plants in patio pots and hanging baskets
http://img713.imageshack.us/img713/1482/composts2.png

[Brutalkillshot5]

Does Bio Bizz have a rating? :)

[Anonymiss]

Does Bio Bizz have a rating? :)
Is it in the full test results? ;)

Which? tend to test mainstream products for the general public — I'd be very surprised if they tested canna-specific items.

My personal feeling regarding Biobizz is that, like all products aimed at cannabis growers, it's very expensive for what it is and that it's probably unlikely to be significantly better than a good-quality mainstream product.

[bigbadbillybob]

Thanks for the usefull thread missy,
i have just gone out and bought Verve "grow your own",
oh the irony ha ha!

[Hempskybergstein]

If you can produce your own I recommend that prior to the above. Its easy, it saves you money and you can bread worms in the process :)
With the addition of chemical ferts added after processing/sterilizing you also run the risk of importation of these (http://en.wikipedia.org/wiki/Fungus_gnat) with commercial composts, and are well known to eat the roots of young seedlings instead of the fungus in the compost which is already suppressed by the fert.
Peat based composts are about to be phased out for the hobby gardener which is why a lot of local councils are positioning themselves to sell you back compost that you have already paid to produce yourselves by throwing it in your green bin ;-)

[mellowed]

Peat based composts are about to be phased out for the hobby gardener which is why a lot of local councils are positioning themselves to sell you back compost that you have already paid to produce yourselves by throwing it in your green bin ;-)

Lmfao. Yep. You pay to get ya garden waste bins empty so they collect it, sell it to the composting company which is usually council run who then churn it all up, mix it with other waste, let it rot for a few weeks then bag it up an sell it for £4 a bag and insist it will contain no plastic which is bullshit. Just look into the back of ya green waste bin wagon an see all the plastic, polystrene, printed cardboard, and bits of other of crap people throw into the bin..........then go to where they empty the wagons and look around. Its full of all sorts of crap you dont want on ya plants. :) I know this as that was once my job.


Wanna know what they do with ya recycled nappies??? Ya wouldnt touch a plastic knife and fork again ;)