The first step in planting is to wet the root-ball of the plant, in case it is dry. If you will not wet it, the plant will not grow. Stand the plant along with its nursery container in a bucket of water for an hour or so, is perhaps is the simplest way to wet the dry root-ball.
Set up a layer of compost in the bottom of the tub or pot over the drainage material. Make sure that it must be of adequate depth, you need root-ball at 12 mm below the level of new compost and the watering space at the top would be 12-25 mm, depending on the size of the container. If you are using soil based compost layer, then stabilize it moderately and for soilless compost stabilize it lightly.
When planting a plant, make sure that its root doesn't disturb. If the plant is in a pot, invert the pot and tap the rim with some solid object until the root-ball slides out of the pot. Sometimes, plants come in flexible polythene bags, just slit it down on one side and peel it off. Always place the plant in the center of the tub or pot and cover it with compost all round it. Use your fingers to firm the compost moderately or lightly, depending on the type of compost you are using, i.e. soil-based or soil less.
Fill the container with compost first, if you are planning to plant several types, such as spring or summer bedding plants. Use trowel to make a hole afterward for each one separately.
Bedding plants are planted with very little soil around the roots, so they are planted bare-root. Before planting any plant, it is important to make sure that the roots are not dry as planting with dry roots will not be of any use. Always plant in deep holes where the roots dangle straight down to their full extent. The depth should be moderate, neither too deep nor too shallow as in both cases your plant fails to survive. Afterward, water them heavily so that the compost settles around the roots properly.
For wire hanging baskets, line them inside with sphagnum moss before planting with one of the propriety basket liners or with a piece of polythene. Black polythene is less visible. Now insert the plants through the wires in the sides of the basket. Cover them with compost and last but not the least, spare some space on the top of about 2.5 cm (1 inch) for watering. You can place basket on a suitable sized flower pot while planting to keep it stable.
While planting growing bags, follow the instruction of the maker and make holes in the top of the bag. Never attempt to make drainage holes in the bottom of growing bags. This means that you have to be very careful while watering the plants in bags as to prevent having saturated soil. Completely flat and leveled surface is required to place the growing bas on.