Something is digging up my dill and chewing it off to the roots. Any idea what it is?
Voles or mice are the likely culprits. These articles will help:
https://www.gardeningknowhow.com/plant-problems/pests/animals/vole-control.htm
https://www.gardeningknowhow.com/plant-problems/pests/animals/garden-mouse-control.htm
I purchased some dill plants that had been left in small seed starter pots too long. Plants are about 2 feet high and started budding. I cut off the dried up leaves and repotted them. I also pinched the buds. Question: Do you think this will be enough?
These articles should help: https://www.gardeningknowhow.com/edible/herbs/dill/tips-on-how-to-grow-dill-weed-plants.htm
https://www.gardeningknowhow.com/edible/herbs/hgen/making-herbs-bigger-through-pinching-and-harvesting.htm
I am growing a dill plant in a pot on the deck and it is about 9 inches high now. How high should I let it get before cutting?
Dill can be mammoth dill, fern leaf dill and regular dill. I typically don't start harvesting dill until it's at least a foot tall, and I never take more than one-third of the leaves at any one time. This article may help as well: https://www.gardeningknowhow.com/edible/herbs/dill/tips-on-how-to-grow-dill-weed-plants.htm
There are caterpillar type bugs on my dill. They are very small. Are they good or bad bugs?
I am uncertain of the pest that is attacking your plants, but caterpillars and worms can be typically killed either by using Bt or neem oil. Here is more information: https://www.gardeningknowhow.com/plant-problems/pests/insects/prevent-caterpillars.htm
https://www.gardeningknowhow.com/plant-problems/pests/pesticides/neem-oil-uses.htm
What will happen if I cut off the flowering head when it first appears?
It will help it to keep producing the frilly leaves for a little while longer, though once the flowers appear, some of teh flavor is lost in the leaves. In the future, it is best just to keep the plant well trimmed so that it does not have a chance to produce flowers.
My dill is maturing quickly; what do I do to get the same "dill weed" that they sell at the store? They are very tiny pieces. How do I get that? I want to put some up for future use. Thank you.
I think you are probably talking about dill seed that you can buy in the store. That's what you see on the ends of your dill. The ends look rather like feathers with tiny seeds attached. I regularly plant this lovely herb in and among my cucumbers, not only does it smell wonderful, I have fresh dill on hand for my pickle recipes and dill is also a great insect repellent.
See this article for tips on how harvest and preserve your dill:
https://www.gardeningknowhow.com/edible/herbs/dill/tips-on-how-to-grow-dill-weed-plants.htm
My plant was doing well, but now it's dried up and weak. It loks like it's dying.
Dill is a cool weather crop. Mine has turned all brown, too, after producing a nice crop. I cut it back just to experiment but I do not see any new leaves developing. They drop seed so you may have more than you can use next year!!!!!