To get the best out of your plants, a regular application of plant food can pay dividends – more flowers and fruit, bigger vegetables, and healthier plants. The choice can be bewildering, with the shelves stacked high with all types from specialist fertilizers made for one plant, such as orchids, to all-purpose feeds, to specific chemicals and organic alternatives. By the end of this blog post, you should be able to ascertain which bottle or box you need to home!
Firstly, a little bit of science: The main 3 nutrients that all plants need to live are Nitrogen, Phosphorous and Potassium. Nitrogen encourages leaf growth and greening up, Phosphorous helps roots establish, and Potassium increases flowers and fruit yield, whilst also increasing disease resistance. If you check the label of any plant food, it should show you an analysis of what percentage is Nitrogen (N), Phosphorus (P) and Potassium (K), (usually shortened to NPK). So, a root building feed such as will have this ratio on the label: 3:7:0, meaning that it contains a 3% nitrogen, 7% phosphorous and no potassium. The label might also mention any trace nutrients included, such as Calcium, Magnesium and Sulphur that plants only use minute quantities of.
Most plants will benefit in the growing season, from a balanced fertiliser such as Growmore (7:7:7), that will benefit the whole plant. Growmore is a granular feed that can be applied as a top dressing or worked into the soil, whilst is a soluble or liquid food that can be watered in. Most plant foods need applying several times throughout the year, as directed on the packet, but there are also controlled release pelleted feeds that last for 3-6 months, which some gardeners prefer. Organic feeds are also available for a number of uses, either food, or traditional feeds such as blood, fish and bone.
There are times , that you need to provide a lot of one nutrient. Tomatoes are a good example of this, as once the first flowers have set, they need a high potassium feed to encourage the plant to produce more flowers and fruit. Tomato food, which comes as a dilutable liquid, provides this. More recently, Tomato food (6:3:10) has been widely used on summer bedding plants, as it keeps the flowers coming. Other examples are Sulphate of Ammonia, (21:0:0) which is a high nitrogen feed for leafy vegetables, and Bonemeal, which is great for adding to the planting hole when you are putting new plants in, and applying to lawns to make strong root systems.
Some plants have needs, and one group of plants that need their own food, is acid-loving shrubs, including Camellias, Rhododendrons, Pieris, and heathers. They require Ericaceous feeds, which you’ll usually find in pink labelled packaging, and which again come , liquid and slow release. These acidify the soil as well as feed the plants. Lawns also have their own range of high nitrogen, liquid or granular feeds such as Evergreen Extreme Green, as well as combined feed, weedkiller and options.
When to feed
If in doubt about when is the right time to feed, always check the packaging – this will tell you the optimum time. However, don’t give feed to hardy plants in the Autumn, as this will produce young, tender growth that can be susceptible to frost. Instead, give a topdressing of bonemeal to boost the root system.
