if by regular soil you mean fine peat-based soil, then yes you will water more often. You can tell when it needs watering by holding the pot and testing the weight, however it might take some practice to get used to it. Start out holding it up and judging if it needs water, then stick a chopstick into the soil to see if you're right. If after 20 minutes or so the chopstick is dry where it touched the top two inches of soil, then you were right- water away. If the stick is damp most of the way up to the soil line, then wait a day or two. Pretty soon you will know as soon as you pick up the pot. For a plant that needs drier soil, wait longer and vice-versa.

You may find yourself watering two or three times as often as with 'regular' soil, but that's ok. A faster wetting/drying cycle helps to grow a dense network of fine feeder roots.

Most plants can thrive in this soil if watered per their needs.

4. IME yes.

5. No.

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