When the cyclocross World Championships conclude at the end of January / beginning of February (depending on the year) many pro riders will hang it up for the season. For you amateurs, your local series is winding down too.
Regardless of your skill level, it's important to take care of your equipment during the off-season, especially your cyclocross tires. This is especially true if you act as your own mechanic.
Don't just throw your muddy, wet, and dirty wheels in the garage! If you do, you might not like what you find next Fall when the season starts up again. A little TLC and prep now will keep your race wheels in good shape:
Clean and dry tires before you store them
Make sure tires and wheels are clean and dry before you store them. If you leave wet tires in damp wheel bags in a dark corner of the basement, mold, mildew, or dry rot can take hold, damaging your expensive tires.
To prevent this: clean, wipe dry, and then get the wheels and tires out for some sunshine to ensure they are completely dry, before you put them away in storage.
Remove sealant if possible, or rotate tires periodically to prevent sealant from pooling
If you don't plan to ride a tubeless wheel for a while (which would distribute the sealant throughout the tire when it spins) you might want to remove the tire, wipe out the tire sealant with a rag, and then store the tire separately. Mount it up with new sealant when you're ready to ride it again.
If you plan to leave tubeless tires installed with sealant in the off-season without riding them, "rotate" them periodically so that the sealant doesn't pool in one spot for a long period of time. You can accomplish this by rotating the valve stem to 12 o'clock, 3 o'clock, etc. throughout the off-season. Just give them a turn periodically.
If you've applied a tire sealant inside a tubular tire, you can try to remove it by removing the presta valve core and then squeezing it out through the valve. If you can't get the sealant out, as with tubeless, make sure to give them a spin periodically so the sealant doesn't pool in one place.
Store your wheels in wheel bags
Keeping your wheels in wheel bags is an easy way to protect them from abrasion and sunlight. Most high-end wheels come in wheel bags, so put them to use. This can protect your wheels and tires from sharp objects in your basement or garage.
Many wheel bags also have straps or handles, which can be used to easily hang the wheel bags on a hook or peg, getting them off the ground where they are easily damaged.
Keep tires inflated in the off-season
Most tubular tires have latex inner tubes stitched inside. We want to avoid having that tube stick to itself in the off season. Avoid this by periodically topping off tire pressure - you only need 10-20 PSI to help the tire and tube keep a round shape.
This is also a good reason to hang wheels, rather than allowing them to sit on the floor. If you forget to inflate, the tire won't become folded.
Store un-glued tubulars on a rim
You might have left over, un-used tubular tires that you kept as spares. If they are boxed, it might be better to un-box them, inflate, and store on a rim (even if you aren't ready to glue/tape.) This will help avoid creases in the tire sidewalls.
Avoid furnaces, hot water heaters
Store everything in a cool, dark, dry place, and away from things like furnaces and hot water heaters. Those household appliances can prematurely age tire rubber and sidewalls.
Don't wait until the last minute to remove end-of-life tires
All tires have a lifespan. If you have some that have reached their end of life, remove them from the rims immediately at the conclusion of the season. This will allow you to remove all the old tubular tape/glue and inspect the rim surface without the tire in place.
This prevents unpleasant surprises when you are gluing / taping new tires at the start of the next season.