If it's only one cell that's broken you can stack two of them together with an undamaged cell over the cracked one. They'll last longer if they are not exposed to extreme heat or cold.
Karyn

Larry, Did you try duct tape? Like you, I reuse everything and that's what I've been using this year. It hasn't really been long enough to say whether or not it's actually working, maybe 2 weeks or so?, so don't consider this a ringing endorsement.

Lime

I double mine up like Karyn...

I use masking tape and it works fine since I'll be potting them into 3 1/2" pots in a few weeks. I'm a cheapskate too!

Deanna

Being your typical chea...er..."frugal" (yeah, that's it) gardener, I'm a cell-pack reuser, too. Both masking tape and duct tape have worked just fine for me. Kept the things together for several seasons. The only time I totally give up on a cell pack is when the thing literally shreds into plastic shards in my hands while I'm cleaning it. :( Even then I'll glance at the masking/duct tape and wonder....Hmmmmm? :)

I have found that I am not using (or reusing)individual cellpacks as much; I found that I was moving "celled" seedlings into larger 3in pots (or yogurt cups, or whatever)anyway to grow on before it was time to "go outside". So I have started germinating most seeds as a group in those larger square or rectangluar inserts that fit maybe 6 or 8 to a flat (the seedlings do come up all bunched togther though)and then carefully pricking them out and putting them in the 3 inch pots at that point. This maximizes my limited grow light space, although it does then put a squeeze on my window sill space for the pots to grow on because there are so many seedlings! I have purchased one of those pop up plastic greenhouses so I can get hardier seedlings outside to that sooner as it does get crazy around here with seedlings perched on every available horizontal surface!

Next time in the hardware store, ask a clerk to show you the metal foil tape. Cut only enough as needed for repairs. Hide the roll when done. It isn't cheap but it is a good mending tape.

Thanks for all of your thoughts. I own duct tape...even thought this is not for ducts, and I had a duck taped down once but it flew away...so it doen't always like up to its name (just another quack product.) ha ha..

I do also possess the metal foil tape which IS intended for ducts.I am not sure that I would use this to repair a 20 cent plastic cell though. A roll of 100 feet cost about 7 bucks. So this will be saved for my dear repairs. (pun intended)

Well I am off to find some quack tape and see how that holds up or if it just shreds into feather like strips.

CrAzY LaRrY

Duct tape don't work on ducts because it dries out, becomes brittle with age and breaks down. Metal foil tape is what professionals use to seal ducts in hvac systems cause it holds well and lasts.

I didn't say to wrap the whole 20 cent plastic cell in foil tape. One small strip (like a mini bandage size) should hold the water in and stay in place. A quickie repair until the plant gets transplanted. Should work if the plastic is dry when the tape is applied and pressed down well.

Liked your jokes tho.