Olson's beautiful fall garden mums placed into a pumpkin fall planter. Unlike mums found in a florist’s shop, garden mums prefer cooler temperatures and continue blooming well into fall. Can mums survive frost? Yes, under the right conditions. Mums should bloom throughout fall until a hard freeze. Deadheading spent blooms encourages new ones to flourish. Insulate mums for colder weather by spreading a couple of inches of mulch or straw over the beds.