This is the time of year to collect and store orchid seed and if the plants are not ours, we always get permission from the landowner to collect seed. The seed must be fully ripe, which means that the seed pods have swollen, matured and started to turn from green to brown, but if you leave it too long the pod will split and the seeds will be gone. The Dactylorhiza seed is fully mature and ready to finish the drying process. These Greater butterfly orchid pods are still green, so the seed inside is still forming and maturing.
Keep the pods in a paper envelope at room temperature until they are thoroughly dry. Split the pod open on a clean sheet of paper, greaseproof paper or foil. Orchid seed is very tiny and will cling to anything damp or plastic, or to the glue on an envelope.
Sieve out any debris using a tea strainer. Fold the paper and pour the seed into a small glass pot or jar. A greaseproof paper envelope is also suitable, but seed does tend to get stuck in the folds.
The seed then needs to be dried again. In a laboratory this is done in a dessicator and the resulting relative humidity can be accurately set, the aim is 12-14%. At home it is done with dried rice. Dry a tray of rice in the oven at 105 degC for 3 hours, allow it to cool. Use a kilner jar or similar with a tight fitting lid and half fill the jar with the rice. Push the bottle of seed into the rice to stand upright, leaving the lid loose or off, so that water can gradually move out of the seed. Seal the Kilner jar and leave for 3-4 days and then tighten the lids and store in an airtight jar, in the fridge.
Seed saved this way will remain viable for many years. This method is suitable for any seed that you want to store e.g. flowers, or veg seed from your garden and they will keep much longer than if you leave them in an opened packet in your shed. You can then use them yourself next year or share them at your local seed swap.