At the 2023 Oxford Real Farming Conference, wheat bran was mentioned as a possible substitute for perlite, to assist with drainage. On 23rd March 2023, I sowed two trays: one with pure woodchip and the other a mixture of 1 part wheatbran to 5 parts pure woodchip. I sowed the trays with Tagetes ‘Orange Boy’, Clary sage (Salvia sclarea) and Chinese violet (Orychophragmus violaceus).
The ‘Orange Boy’ germinated really quickly and was pricked out on 13th April and again later on the 27th. On the 30th April the germination rates and growth of the other two species was compared.
The chinese violets in the wheatbran/woodchip mix were much larger than in the pure woodchip mix. However much more clary sage and Tagetes had germinated in pure woodchip.
As well as this test, I sowed some cardoons into modules using the same two substrate mixes on the 23rd March. 15 modules with each mix were sown with a single seed. The germination and growth rates were compared 2.5 weeks later.
9 out of 15 seeds had germinated in the pure woodchip compared to 7 in the woodchip/wheatbran mix. However, the seedlings in the wheatbran mix had much larger leaves.
Observations and conclusions
- None of the seeds performed particularly well, except for the Tagetes marigold.
- There were some small white roundworms in all of the trays that could have been large nematodes. There were much more of these near the chinese violet roots than by the clary sage roots.
- The box of wheatbran and woodchip mix that I stored outside went mouldy.
- The chinese violet seemed to prefer the wheatbran mix but the other two species performed better in pure woodchip, in terms of their rate of germination.
- Cardoons seemed to grow better in woodchip mixed with wheatbran but to germinate slightly better in pure woodchip.
- Wheatbran may be a useful addition to woodchip for growing seedlings inside the home or in conditions that aren’t humid.
- It is probably worth experimenting with different ratios of wheatbran to woodchip as well as finding out why some seeds seem to prefer the mix, but not others.
Edible Eastbrook 