I've raised strawberries for more years than I care count, & from what you describe, Badplanter, I think Deborah's guess is right on the money. Most strawberries are at their peak production during the first 3 years... maybe 4, depending on the variety. After that, they might still bear fruit, but the quality drops noticeably. (Are your berries also smaller than they used to be?)
Old
plants will still send runners out & you should let them do that, using the babies from those runners to start building new strawberry beds (pots/towers) with. (They'll
flower & make nice berries next year.) You might want to thin out your strawberry bed this fall, after the new runners have had a chance to dig in & set down their own roots.
The way to tell if a
plant is old (3+ years) is by its roots & the crown. They'll get quite thick & woody after a couple years (the leaves may even be smaller). Toss those out, leaving the more tender crowned
plants to go for another couple years.
Since I couldn't bring myself to throw away the old
plants that were in the strawberry bed when we moved here 3 years ago, (they were "alive"!) :rolleyes: When I thinned the bed out, I put all the old
plants in an out-of-the-way spot in the yard, & let them do whatever they wanted! Last year they made berries (not very sweet though), & sent runners out like crazy. This year my daughter built quite a large strawberry area for herself, using all the new
plants that had sprung from those old maids... her berries are terrific!
It might sound like a lot of work, but believe me when I say it's well worth the effort & you won't be sorry! This is the last year for the strawberries I've got here, & I'm letting some of them throw runners so I can replace them with the new babies. I want to work it around to where I have a "new" section every year, instead of starting over every 3rd or 4th year, as I did when I first started working with these.
Good luck!