Compost trials
Tuesday 25th October 2022Melcourt Sylvagrow – peat-free
Dalefoot Wood compost- wool and bracken, peat-free
Levington Professional Tree and Shrub (TPMC) peat-reduced
Humax – peat-reduced
Bathgate – peat-based
John Innes No 1 and 2 – peat-based
Over the last three years I have been experimenting growing bulbs and summer bedding in the various composts we sell. It started out as a trial to see if the mix bags of bulbs offered by Taylors Bulbs really worked. I am sure, like many other people, I buy a bag with a lovely shiny cover only to open up and find not very exciting-looking brown desiccated bulbs and wonder if they will ever turn into the beautiful plant photographed on the package.
I started with Taylors Coloured Themed blends and the first year I was delighted all the bulbs came up and filled my tubs from February until May when I replanted with summer bedding. These desiccated bulbs seemed to grow whichever way up and I have been using these multi bags ever since. I now plant the bulbs into different composts to see how well they compare.
Compost for Bulbs
In 2021 I planted bags of bulbs with Taylors bulb compost, wool compost, Bathgate and Humax general multipurpose compost, Melcourt Sylvagrow peat free and Levington Tree and Shrub professional compost. The bulbs appeared from early March until mid-May but the bulb compost was very poor and my pansies planted on the top hardly grew either. The wool compost and Tree and Shrub compost proved the best, the Humax was also disappointing.
Summer Bedding
I have been experimenting over the last two summers using Melcourt peat-free, Bathgate and Humax multipurpose, Levington tree and shrub and wool compost.
General feedback from 2021 – Melcourt grew very slowly and plants half the size, Levington did well but ran out of food by the end of the summer, Humax and Bathgate did the best
Results for Summer 2022
Having spoken to Melcourt regarding peat-free I was advised that, to the make of the compost, you need to feed and water it more. I planted one tub with just Melcourt peat-free and one with Melcourt peat-free and John Innes No2 which was to give it more food and I hoped moisture retention.
Bathgate and Humax were the best. The plants grew brilliantly and I watered all the pots the same. Melcourt peat-free was again very disappointing to start with very short plants but they did keep going to September, Melcourt with John Innes No2 did very well to start and mirrored Bathgate but lagged by the end of August, Levington grew well but by the end of the summer had run out of food. The wool compost was planted up later so unfair to compare but grew very well and certainly retained the moisture better during the very hot spells.
Conclusion
If using peat-free I advise adding John Innes No 2 or 3 which will help add food and retain the moisture. The wool compost is very encouraging and I will continue to trial this; it’s definitely worth trying if you want a peat-free option. Levington peat-reduced works very well as did the general multipurpose composts.
I will continue to stock the composts listed above and will continue with my trials. Going peat-free is a huge challenge for garden centres and nurseries with each batch of compost a slightly different make up. The main tip I can give is to add extra food and I am afraid you will have to water more. It’s also advisable to mulch your pots to keep the moisture in, if they do dry out it takes much longer to rehydrate and some peat-free composts create a crust on the top when dry which can be difficult to penetrate.
In the nursery we find the peat-free dries out very quickly especially in small pots and it is sometimes difficult to water evenly through the pot creating an ununiformed root structure. We also feed our plants more as the nutrients leech out, once a crust has formed it can take a long time and a lot of water to rehydrate the plants. Thank goodness for the rain today.
Good luck and I would love to hear your experiences.