I think Lady D here is being a little over-cautious.
1. Many strains are mold-resistant. Quite a few are susceptible to mold. Find out about your strain.

2. Gray mould is the biggest problem but you will need a couple of days of rain and then a humid atmosphere to allow the spores to take hold. If it pours and then brightens up such that the plants dry out, then there is little chance of mold.
3. You need to be very careful in the last 2-3 weeks of flowering, especially if there is cola formation and the buds are tight. If heavy rain is forecast then find some large see-thru plastic sacks (like large garbage sacks) and put them over the plants. Even if they don't protect the plants fully you will avoid getting the main colas wet. DO NOT cover wet plants ! As soon as the rain passes, remove sacks ASAP !
4. Trichomes washing off ? Its not a problem. You would need a week of heavy rain, and then there would be other problems with your plants. Yes, rain will dislodge some trichomes but its not significant.

All the above assumes you are growing outside in soil. If yer plants are in pots or bags and you can move them to a protected area in case of storms, then do it !
Finally, IF the weather is bad and you are near harvest, watch your plants carefully. Most times you will see mold starting (but sometimes it starts inside a bud ). Now get your knife/scissors and go to work on the infected bud. Chop all gunk away and then some. Try to do this with a plastic bag surrounding the cola/branch. Why ? Because you drive spores into the air, and onto to other unaffected growth. Be a good surgeon !
If mold affects several sites simultaneously AND you are near harvest, chop your babies down, remove mold and get those babies dry fast ! When they are dry, hang them for drying out the buds etc.
Finally, finally, DO NOT SMOKE mold !!! It will f%#k up your lungs and is very bad for your health. I've seen mold sometimes in dried bud. The bud just crumbles between yer fingers...you'll know its not right yourself. Rotten bud.
Good Luck.
houdini Reviewed by houdini on . is rain a problem for buds? When buds are fully formed....for me in about 4-6 weeks.....is rain a concern? .....if the sun dries the buds I guess its okay, but what about a big fall rain? thanx..I'm a rookie Iris Rating: 5