Just a guess, but I would rather think your plants have had too much water. I live in a very humid area and I often get that kind of effect when our humidity levels have been off the chart. I love celosias, but have nearly given up on them in my climate.

I work at a large scale commercial nursery and I'll give you my two cents if you'ld like. That blanket statement that plants in cell packs are bred to be small is partially true, but not because the growers are trying to "trick" the consumer. It's a logistics problem. The more plants a greenhouse can fit on a bench the more plants can be sold in the shortest amount of time. If a fast growing annual...like celocia or impatiens get too large before they are ready to bloom then they wouldn't be cost effective for the greenhouse to grow and sell. So we have a little trick to solve the problem. It's call growth inhibitor chemicals and specialized fertilizers. Not the kind of chemicals that "poison" the plants, but naturally occuring chemicals (synthetic hormones sort of) that are stepped up a notch. They make the plant more compact with super flower-power which makes the consumer's eyes pop out at the store. They take the plant home and somehow it looks much punier in the garden than it did at the store. Most plants will eventually "grow-out" of these chemical treatments on their own, but some just never quite grow to their full potential. Celosia is so easy to grow from seed. It almost grows on it's own straight out of the package. I recommend growing this particular annual from seed because you can choose any variety you like that will fit perfectly in your garden scheme. And they do grow so quickly and flower quickly too so your reward is very short in coming.

I just did a Google search to find out why my 18" tall Celosias have this problem - beautiful, lush foliage but no blooms! Glad I stumbled on your post, and am encouraged to think they'll eventually come through. :-) While I didn't start mine from seed, I discovered in late spring that some "volunteer" seedlings were emerging from an outdoor pot I'd had some gorgeous, unusual colored Celosias (bright pink with burgundy-tinged foliage!) planted in last year. They were purchased as young (blooming) plants from a nursery. Naturally I was thrilled to see they'd evidently self-seeded and left them alone. Over the past couple months they seemed to thrive, growing taller and thicker - but alas still no flowers! In my impatience I started pouring on liquid bloom fertilizer, but still only continuously growing foliage. So thanks to your post I've now come to think that that organically seeded Celosias will just take their sweet time about blooming - roughly 90 days, haha! So looking forward to the return of those gorgeous, feathery pink flowers for at least the last couple months of summer and fall anyway! Thank you for following up on your post; you've helped at least one other discouraged gardener. 😊 [To anyone starting your own harvested seeds indoors - might want to sow them in Jan to give them a head start! 😉]

Celosias don't bounce back from stress. They can't be allowed to dry out or to become root bound. Their response is to stop growing and put out flowers way before they are ready. I think there's a good chance that your celosias are in this stage, and if they are, I'm afraid they will never get up to a normal size. I learned this lesson myself a few years ago with some trays of celosias that I started too early, and they became root bound before I could get them in the field. It can't hurt to pinch the blossoms off and see what happens. ThinMan