The growing medium in which you bought the plant may easily have become very desiccated. Water may largely drain out round the edges of the pot, giving the plant little opportunity to absorb it. In the garden centre plants are watered every day. At home it may often be left for a few days, there are no water reserves in the soil, so the plant gets nothing to drink and either dies or becomes poorly. When a plant’s roots have pretty much filled the pot it pays to stand the container in a deep saucer, water it thoroughly and let it stand in the water for an hour or two so the compost is thoroughly moist. Then replant it and give it a thorough watering as soon as it is in its new home. It pays to water regularly for a few weeks whilst the plant establishes itself in its new home, every day if the weather is very hot and dry and your garden soil is not retaining moisture around the plant.
When planting you should make the hole the right size, the soil line of the plant in the pot should be the same when it is in the ground. Many shrubby plants are grafted onto another rootstock and if they are settled more deeply into the earth the junction of the graft is below the ground and may start to produce another plant entirely. (Roses are a prime example of this issue.) There is always an exception to the rule, Clematis are generally buried more deeply – planting instructions are usually on the label when you buy these plants.
In many cases the plant has been in the pot in which you bought it for some time (especially by the end of summer). It may have become ‘pot-bound’. This means that the roots are crammed in and have circled tightly round and round. Even when it has been transplanted the roots can continue to grow in this same circle. They fail to reach out into the soil and therefore get little in the way of nourishment, or even water. The solution is to encourage the roots to move outwards by teasing some of them away from the tight packed root-ball. In all cases it’s worthwhile to spread the roots at the base of the container outwards to encourage them to reach into their new environment.
If you put your plant into another container the plant will use up the nutrients that are in the compost within a few weeks. After this time you will need to provide the plant with ‘food’ – a general purpose rose feed is the classic recommendation. There are many others! You can choose between short term and slow release fertilisers (these are more expensive but once having applied them it is job done for the season). Even in the garden plants will flower better if they are provided with extra nutrients from spring till the end of summer. The foliage of plants in nutrient-poor conditions can deteriorate quite rapidly.
Some types of plant only flower once a year, lilacs and peonies are examples of this. Other plants will continue to produce flowers if the old ones are promptly removed. This is the case with most modern roses and many popular herbaceous plants. If you regularly ‘deadhead’ by snipping off the bloom as it begins to fade the plant will make more flowers for you.
It is much less work than it sounds to keep your new plants alive and happy! Enjoy.
This Longacres Blog post contributed by Susan A. Tindall