its hot and humid here and drying things after freeze percip is a real issue. could a sealed drying unit with filters be used? it has thermostat which goes down to 30C. but it really gets herbs dry as bone, so thought maybe this would work? am slightly worried about evaporating it and losing it all though, or is that dumb?

What about desiccant like silica gel drying? Need very dry product for weights.

Nothing is going to evaporate at 30°C, but at around 45°C your spice will begin to melt so be sure the thermostat is accurate.

Silica gel will also work, but it will take much longer. You might try leaving a pouch of silica gel in the same container you store your spice in for a few days or permanently. Just figure out a away to keep them from contacting each other.

Having the pouch sellotaped to the inner lid of the jar or container would probably be sufficient.