Updated 2026-08-26
Memory foam is a sponge that must never act like one. Every cleaning rule for it descends from that fact: minimal liquid, zero heat, maximum drying.
The banned list, first
No steam cleaners, heat plus moisture degrades the foam structure and voids warranties. No soaking, saturated foam takes days to dry and often never fully does. No harsh chemicals, bleach and ammonia break down polyurethane. No stiff scrubbing, which tears cells. The gentle path is the only path.
The maintenance routine
Vacuum with the upholstery attachment monthly, slow passes, seams included, this is the workhorse step and it is completely safe. Quarterly, add the baking soda treatment: sift a layer on, leave it several hours to pull moisture and odor, vacuum thoroughly. Between the two, most foam mattresses stay fresh with zero liquid ever touching them.
The spot cleaning method
Mix a drop of mild dish soap into cool water, dampen, not soak, a cloth, and press the stain gently, working from the edges inward. Follow with a cloth dampened in plain water to lift the soap, then press hard with dry towels to pull moisture back out. For urine, the enzyme method applies with the foam cautions doubled: light application, aggressive extraction.
Drying is the whole ballgame
After any liquid, give the foam hours under a fan with airflow across the surface, a full day for anything beyond a small spot, and confirm bone dry before bedding returns. Moisture that stays writes the mold chapter, and inside foam it stays by default.
Prevention beats every method here
A quality waterproof protector converts foam’s greatest weakness into a laundry cycle. Fit one today, and the next incident never reaches the foam at all. When cleaning stops being enough, the routing from $85 is always open.