Method

1. Choose a container for the shrub. This should be large enough to accommodate the plant comfortably, allowing it plenty of room to grow. If you are re-potting an existing containerised shrub, make sure that the new pot is about 5 cm (2 in) larger in depth and diameter than the previous one. Previously used containers should be thoroughly scrubbed inside.
2. Select the right position for your container before planting up, as they can be very heavy to move afterwards. Placing the pot on blocks or 'feet' will ensure that the compost can drain freely.
3. Place a layer of broken crocks over the drainage holes and then add 2.5 cm (1 in) of coarse gravel or other drainage material.
4. Add some loam-based potting compost enriched with a slow-release fertilizer. Loam composts are preferable to peat-based composts as they are nutrient-rich and so the shrub will require less feeding over the subsequent years. They also tend to dry out less quickly that peat composts. If you are planting rhododendrons or other lime-haters, use an ericaceous compost; this is also useful if you want to produce blue flowers on hydrangeas.
5. Place the shrub in the pot and fill the container, making sure that the soil mark is level with the compost surface. The compost level should be at least 4 cm (1 1/2 in) below the rim of the pot to allow room for mulching and watering.
6. Firm in gently, taking care not to damage the roots.
7. Water thoroughly.
8. The pot should then be dressed with a generous layer of horticultural grit to help retain moisture and improve the appearance of the pot.