We really can't help you with the information you've provided. The usual problems would be over- or under-watering, too little or too much light, problems with the potting medium consistency or ingredients, over fertilization, unchecked insect and/or disease issues.

I'll take a guess here - you planted dill plants? Try direct sowing seed for better results.

FataMorgana

How warm is it where you are at? The heat will make Dill set seed and die.

Also, "you are planting in pots" are you removing the dirt and the plant after it died, or just the plant itself. Dont give up, empty your container completely...soil and plant....refill with new fresh soil, get you some seeds, be patient, and watch it grow. Have FUN!

I have a potted Dill plant in my front living room window it gets plenty of Sun and is growing well. This is what it looks like. Should I be cutting some of the longer stems down? Or should I just continue to let it grow taller?

Would you mind to share how much and how frequently do you water the plant?

The long stems are flowering stems. Cut them back and use them in cooking. I’m guessing you’re in the U.K. or Ireland. In which case your window won’t have enough light for it. It really needs to be outside. Personally I find dill tricky in our climate. It is often thin and wispy and bolts quickly. You need to sow in succession. I’d try again by sowing seed outdoors in good soil.

Thank you for responding to me!! I took your advice and cut the long stems back! I live in the state of Wisconsin in the U.S. There was plenty of sun in my living room window in April and May, but now the sun has shifted, so now I have the plant under a grow light. It is doing okay. I can see that dill is tricky! I have never tried it before!

I water the dill plant about 4 to 5 days, keeping it damp not soaking wet!

Ok. I misinterpreted your location. Do you have any outdoor space where you could sow some more seed either in the ground or in a pot? I don’t think your current plants are saveable by either feeding or watering. Dill is a short lived annual and once it’s flowering it’s on its way out. (I say ‘plants’ because what you have is a clump of seedlings rather than a single specimen. Hence they’re a bit crowded. Weak and stunted)

Thank you!! I will try that!!!

I'd heard the same as others here...that it doesn't like to be transplanted..that you'll have better luck starting from seed, and then having it stay put.

Thank you Lynn!!