It really doesn't take much. You don't want to bake the stuff, just make it a few degrees above ambient and you won't get condensation, because you're well above the Dew Point, & the RH will be low.a couple of low watt bulbs in there
Air movement and daylight are good, to help stop spores growing, though obviously fresh air ingress gives you more air to process.
CaCl is effective as a dehumidifier too - as sold in "Poundland"!