New rootings should be in as small as a container as you've got, preferablythrough which you can see the roots so tha tyou know when to pot them. With most plants, I use a plastic drinking cup with holes in the bottom until it's busting out of it, and then put it into a 4-inch pot. With some I put several into a 4-inch pot when they're each too big for the cup.

In my experience, most plants do better at just-about potbound. I haven't found one that likes to be swimming in a pot.

Watering frequency depends on the plant, the pot, the temperature, the humidity and the sunlight. I wouldn't go by number of days, but by how the soil feels and what kind of plant you have. Most of them need to be watered when the top 1-2 inches of soil is completely dry. A few can go a day or so beyond that, and it's almost always better to underwater than to overwater. Peace lilies need to be kept moist but are easily overwatered. You may find that your spider needs water sooner than your philo, so I'd check them every day until you know them.

I don't know about spiders and babies, beyond that they absolutely won't have them if their pot is too big. :)

Good luck to you!

Jude

Hi Jodie, First, though Petunia is a beautiful, sweet-smelling plant, it's an annual..They do best outdoors. If you decide to grow it as a house plant, keep in the sunniest window, in a cool room.
If you can place outside until autumn, do so. Otherwise, place in a south or west window.

How many stems do your cuttings have? For instance, are each one stem or several? Once they root, pot in a small container. Though most ppl do not have peat pots around the house, what I been doing is placing cuttings into these pots, then settting into a 4" pot.
Depending on the amount of roots makes a difference, but I wouldn't repot larger than a 4" pot. In fact, if roots are small, a 2 or 3" would work best..at least until roots fill container, then increase pot size.

Do some of these plants do best potbound? Are you taking after roots are established? If so, I find the Peace Lily does best when a bit potbound. But, don't overpot any plant..When you need to repot a house plant, the normal range is 1-2 sizes up. So, if you have a plant in a 4" pot, and 'need' to repot, go to a 5 or 6"..

Spider plant babies..it depends..I have a tiny spider plant attached to the wall on the side of a west window..it has about 12 leaves, yet it shoots out babies. The larger the plant, the more babies it'll get.

Watering...the best time to water is when soil feels a bit dry..Not bone dry, but crumbly dry. Plants usually need more water in summer but it depends on your house..if your home is air conditioned, kept cold, soil will take longer than it would in a warm/hot house. The best way to tell is by sticking your finger into the soil. If your finger comes out wet/moist, wait a couple days and recheck. If it comes out dry, then water..Another way to tell is by lifting the pot..When soil is dry pot will be light in weight..when wet it's heavier. Since you're new at growing plants, it's a good idea practicing lifting pots when dry and wet to distinguish the difference.

After you get the hang of basics, you'll need to learn about fertilizing..This should be done during growing season from spring till autumn. But I'm jumping the guy..lol..sorry..Good Luck, Jodie.... Toni