I recently found out that you are supposed to rotate your mattress “regularly” (whatever that means) but, according to bedding manufacturer Saatva, there are exceptions “when it comes to mattresses with particular features such as zoned support targeting specific areas of the body for special comfort or support.”

Zoned support ,,, hmm. You should flip your mattress over, too, but only if both sides are padded.

Our mattress was so heavy I could never lift it high enough to find out if both sides were padded or not.

Still, no matter how often you rotate and flip, I’m told you still should buy a new mattress every seven to 10 years. We kept ours for at least 15 years (please don’t tell anyone).

Finally, the time had come — for me, anyway.

Husband: “This mattress is perfectly fine. Why do we need a new one?”

Me: “Because Cro-Magnon man dragged our model into his cave when he came down from the trees. It’s an archaeological artifact.”

He held out; I bided my time. When there were big advertisements for Labor Day mattress sales, I struck.

First, I treated my husband to a big lunch and then I suggested we walk it off — around the mall that happened to have a bedding store in it.

After assuring him I “just wanted to take a look,” I found to my dismay that there are a zillion choices when it comes to mattresses: foam, inner spring, hybrid, organic, regular, firm, extra firm, cool, hypoallergenic, king and California king.

After much bouncing, stretching out and lifting demo models, we chose a really firm, lightweight mattress. I was sure sweet dreams would follow.  

Only one thing puzzled me: A fee of $12.50 had been tacked onto the bill for recycling our old mattress, a fee I had never seen before.

My curiosity about this add-on led me to the Mattress Recycling Council’s website. The council claims 15-plus million mattresses are discarded every year in the United States, an average of 50,000 a day, with most of them ending up in landfills.

Now, California, Connecticut, Rhode Island, and soon Oregon, avoid that outcome with mandatory recycling.

 The council site also explains that mattresses are made up of many parts, and there can be a home for each of them.

After a mattress is collected from a retailer, institution or collection site, it is brought to a recycling center, where workers cut it open.

The foam is baled and compressed for use in carpet padding and other cushioning.

The inner springs are turned into scrap that is melted down and reused in steel products.

Cotton and other fibers are turned into insulation or industrial filters.

Finally, the wooden frame is chopped up, and typically gets a second life as garden mulch or biomass fuel.

Some manufacturers are not waiting for the second life. King Koil of Australia, for example, is making its mattresses eco-friendly from the get-go.

The company recently unveiled its Re-Spun collection, which is made from glue-free coils, and plant-based foam, wool and cotton. All this is covered in recycled denim.

As for me, sweet dreams did follow our purchase because I knew our old mattress was doing its part for the circular economy.

I could thumb my nose at Hamlet, who famously lamented, “To sleep — perchance to dream. Ay, there’s the rub!”