justaguy...Okay your comment totally goes over my head...not sure if you are trying to tell me using the old soil is a waste, if using MG is a waste, both, ? I am saying that if your old potting mix has degraded to the point it is no longer suitable that mixing it with fresh mix is a waste. The primary problem with old mixes is that over time the particles of stuff they are made from degrade/decompose into smaller and smaller particle sizes. As this happens the amount of water the mix can hold increases, but the amount of air that can be held in the mix decreases. The amount of air a mix can hold is called air porosity and there are minimum levels of air porosity required for healthy root growth. Many studies have consistently shown that as air porosity decreases, so does plant growth. So, the old mix has broken down into smaller particles and the air porosity of the mix has decreased. If you get a bag of fresh mix using the same ingredients in the old mix they will be larger in size and the mix will have greater air porosity. If you mix the old with the new you are immediately dropping the air porosity of the new mix by adding lots of small particles that will fill in the air spaces between the larger particles. If cost of replacing the mix is a concern then I would definitely suggest looking into making your own mixes at some point in the future when you are able to do so. Buying your own ingredients in bulk and mixing them is generally less expensive in the long run to buying commercially prepared mixes. You can also choose ingredients such as pine bark instead of peat as the basis for the mix. Pine bark will break down over time just like peat does, but it does so much more slowly so if you were to reuse the mix from season to season you would have a mix that maintains favorable air porosity for a longer period of time. This also makes it a good investment. For this season you might wish to purchase as much new mix as you can justify and use it in the containers. For the old containers with older mix you can still use it, but I would advise putting the plants you are most fond of in the new mix and plants you care less about how well they grow into the old mix. In both cases you may find your plants do better if you add a drainage wick to the containers. If you use this forum's search function on 'wick' you will find several threads discussing this.

alaMel, There are as many answers to that as there are answerers. Even variables like your climate and how often you plan to water will play a part in determining which mixes would work best. I'd recommend doing some reading over at the Container Gardening forum. Al's mixes may be a little overboard for growing Morning Glories, but the thread is just packed with useful info that can help you make better decisions on potting mediums (see link below). Here is a link that might be useful: Container Soils - Water Movement & Retention

I don't have experience with it yet, but I am planning to plant both Moonflower and Heavenly Blue Morning Glory together in a large container (so I'll have blooms both during the day and evening). I've been babying some seedlings inside. I'm putting them in a container for a few reasons. One is because the location is one where I have a buried downspout drainage pipe, so putting something in the ground isn't practical. Second, I'm hoping that being in the container will facilitate warmer soil temps for the moonflower and get it going as quickly as possible. The third is that I'd like to try to overwinter the moonflower vine (at least). The intent is to have them climb one of my porch posts and railing. We'll see!

You could give it a severe hair cut and allow it to become a bit shrubbier. Grown inside like that, even with a 'gro-light', it will always be a bit leggy. Good for you for encouraging it to do so well.