Camden Garden Centre is full of tender bedding plants and some gardeners plant them in the garden immediately, gambling that there won’t be any late frosts in their area to kill them off.
Some years they are lucky and they have a really early flush of colour from geraniums, busy lizzies, petunias and fuchsias. In other years, late frosts can occur up to the end of May in some areas of the south and they are not unknown in June in Scotland.
Early planting of tender bedding plants is OK if you are prepared to watch the weather forecast for your area and have sheets of newspaper to fix over the plants every evening in May should frosts be predicted.
Don’t be fooled by any plant label that claims it is ‘half hardy’. That is gardening speak that really means ‘not hardy at all’ – so beware. After you have bought your bedding plants keep them for a week or more outside in their pots or trays to harden off. Up until now these tender plants will have been kept in a heated greenhouse, so they need some time to toughen up the inevitable soft foliage and to get acclimatised to colder nights. A position close to the house on a warm patio is ideal as bricks and paving hold heat for many hours. A covering of newspaper or fleece will ensure the plants are tucked up safely on cold nights when ground frosts are predicted. When planting out bedding, give the plants a thorough watering in the trays or pots the night before planting so they have had a good drink ready for root disturbance and the trauma of new surroundings. Select your plants for the conditions your garden offers. In shady spots buzy lizzies and fibrous rooted begonias will thrive without too much direct sun. So too will pansies, Canterbury Bells, lobelia and coleus. In hot, sunny spots plant those that are more tolerant to drought conditions including geraniums, petunias, verbena and Californian poppy.
All of the plants will appreciate a rich organic soil that has had some Miracle-Gro Soil Improver dug in before planting. This will improve the structure and help the retention of water and nutrients. To ensure the roots can draw on ample plant foods, scatter a handful or two of Rose Plus or Miracle-Gro Slow Release Plant Food over each square yard of soil and rake in.
Take out small planting holes with a trowel, leaving space between each for potential plant growth. Firm soil around the roots with your fingertips and leave a shallow depression on the surface around the stem so that any subsequent watering puddles just above the plant roots without running away. The initial watering in of these new plants is best done with a solution of Miracle-Gro Plant Food or other soluble plant food so you can feed and water at the same time. By applying the plant food over the leaves and around the roots you will quickly help the plant get over the root disturbance and shock of transplantation. The nutrients that are absorbed in the first week will help the plant send out new roots into your garden soil or compost so that it gets established quickly. Stake tall growing perennials such as delphiniums, lupins and monkswood early and tie in regularly as the flower stems grow. Remember to put eye guards on top of any canes that you use.