Parsley is a biennial plant. That means that it lives out its entire life-cycle (seed to seed) in 2 years. In its second year it will send up flower/seed stems which can be quite tall and the seeds can take quite some time to mature. When they do, they can spread far and wide (by wind).

Once the flowers appear, there's not a lot you can do to stop Nature doing its Thing. Removing the flower might delay the inevitable for a week or two, but personally I think you might as well not bother. The plant will do what it's supposed to do, regardless - which is produce babies/seeds, then die. I don't think a couple of weeks will make a huge difference - and it's best to let Nature get on with doing what it does. Besides, once the plant starts to flower and go to seed, the flavour of the leaves becomes more coarse, definitely not as nice as in its first year - but still OK.

BTW, Parsley is one of the so-called Mediterranean herbs, and will do quite well in a hot climate - as I (in the Australian sub-tropics) can testify. It can take a full, roaring summer sun, or partial shade. And it will grow much bigger than most beginners expect! Especially the Italian or Flat-Leaf Parsley (which is Petroselinum neopolitanum - P. crispum is the Curly Parsley).

Also, Parsley doesn't like being transplanted - this is because it has a deep tap-root. Such plants never like their roots to be disturbed (they sulk and bolt to seed early, or just die, to spite you). So repot or replant your parsley ASAP while it's still very young, and next time sow seeds in situ (ie where you want them to grow). Don't hold your breath while waiting for the seeds to germinate - they can take a long time, and you need to be patient.

Wow, I asked for some Parsley wisdom and I got it. Thank you. Given the knowledge of the deep taproot, I'm thinking I should move it out of its little 4" pot as soon as possible, but now I'm wondering... what would be a good pot to accommodate for this? Doing a search on Petroselinum neopolitanum (thank you for that information), shows that the plant can get from 4-8" (10-25 cm) in height, with the flower stems tripling that height. Can I safely assume that the taproot at least match the growth height? Or will it grow deeper? Should I be looking at a 12"(30 cm) pot or something larger? I would imagine that planting in-ground would be optimal, but until I get more herbs and actually formulate a plan for where I want them, I would like to keep them potted.

Thank you, again.

Tap root and plant height have absolutely nothing to do with each other. In a container, your plant will accommodate itself, more interested in the total volume of good, well draining, porous potting medium than depth. You can even cut the tap root off with no problem and allow the plant to quickly branch out laterally.

You could begin your plants in an 8 inch pot and then repot them into something a bit larger later on down the road.

Tap root and plant height have absolutely nothing to do with each other. In a container, your plant will accommodate itself, more interested in the total volume of good, well draining, porous potting medium than depth. You can even cut the tap root off with no problem and allow the plant to quickly branch out laterally.

You could begin your plants in an 8 inch pot and then repot them into something a bit larger later on down the road.

I've had Italian parsley grow up to my knees and more. Roughly half a metre. A mature tap root could be roughly 15cm.

I grew flat-leaf parsley outdoors in SoCal. It does fine, even seeding in the 2nd year.

I suggest you plant your parsley in the garden. That way, you'll have plenty of leaves to use.

Well, thank you all for your tips, suggestions and information. I have both the oregano and parsley repotted into 8" pots which looks at the moment to give them plenty of room to expand. While I would love to put them in the ground, I need to figure out how and where (plus get more herbs to go with them). I don't have a lot of room to work with and the area that I've been planting I've been fashioning into a butterfly-friendly area. I know I can incorporate the herb garden in with the butterfly garden (a local 'butterfly house' has several curly leaf parsley set up as host plants), I just need to figure out how I want to do it.

Thanks again, everyone.