The plants are stable for weeks, unlike when growing cress on tissue paper.
The terrarium consists of several layers in a glass vessel. I used a bottle from dried herbs. From bottom to the top:
- Small stones or glass beads – the recipe used seed glass beads, which I didn’t have. I think cress in the vessel with pebbles looks healthier;
- some soil, I used potting compost;
- cress seeds scattered on top plus some extra soil.
I’d added a few mustard seeds after 4 days to make an extra level (smaller shoots). The roots are also visible near the glass wall, illustrating nicely how the plant grows.