Beautiful Gardens of Doon-60
Fertilizing Annuals with NPK
By SUNITA VIJAY
Well-fed plants are healthier, more productive, and more beautiful to look at. As winter recedes and spring approaches, it is time for the annuals to bloom in full glory. Annuals will fail to put their best performance if under-cared for. What is it that diminishes their spark and reduces the vigorous budding and flowering?
Annuals require three important key macro-nutrients NPK (Nitrogen, Phosphorous and Potassium) along with magnesium and calcium in smaller amounts, and few other nutrients like iron and boron to provide lush green leaves and gorgeous flowering.
The organic compost and kitchen waste/leaf compost have all the above nutrients, good enough to provide annuals robust health. The annuals raised in beds may still not need additional nutrients if the soil has been fed well before planting but the ones in pots require supplements. Each time you water, the nutrients are drained through the hole at the bottom of the pot depriving the plants of required nutrients to bloom adequately.
Benefits of NPK
Nitrogen (N) helps in the growth of the plant, its new stems and leaves. It is a necessary part of chlorophyll. It makes the leaves of the plant green and helps plants photosynthesize. With its addition, annuals become healthy and the stem grows strong enough to bear more buds and flowers. Flowers have always look good against fresh green foliage.
Phosphorus (P) helps in developing flowers, fruits, and the root systems of annuals. If you want more flowers don’t miss out on this.
Potassium (K) keeps the roots healthy and aids flowers and fruits. It provides disease resistance and helps regulate metabolic activities of the plant.
Annuals like Marigold and Petunias require more NPK than any other Annual. Maybe they extract all the nutrients faster than others because of their profuse flowering and short span.
Never indulge in over fertilization
Less fertilizer is good then over feeding. Annuals are tender, have a short life span and fragile root system not strong enough to bear the overdose. Add less, never more, maybe more frequently for best results.
Signs a plant may show due to deficiency of NPK
Plants can’t speak but never fail to convey how they feel. Take cue from their behaviour and changes in their leaves. Be observant to diagnose the deficiency and act fast.
In case the leaves grow pale green or the older leaves turn yellowish or look undersized and the stems are short and weak; it is a sign that the plant has low nitrogen. Use Urea to compensate.
Deficiency of Phosphorus is detected when the leaves turn purplish or develop a reddish tinge. They may twist or turn into irregular shapes.
In case the lower leaves start wilting or turn dead at the edges, it is a sign of low potassium.
How to provide the right nutrients
Organic fertilizer, made from naturally occurring mineral deposits and organic material, leaf mould, kitchen compost (with tea leaves, eggshells etc.) or composted manure, is the best for annuals. It is not water soluble, once added gets released to the plants slowly and provides nutrients for a long period.
Inorganic fertilizers are water soluble, fast acting and are taken up by the plant immediately. Never add too much of inorganic fertilizer. It will burn the plant, damaging it. They are good for a quick boost and fast result, highly suitable for annuals who are always in hurry to perform and wither. Synthetic fertilizer will never help in improving the soil fertility for a long period.
How to add NPK to the plant
Plants absorb nutrient much faster through leaves than through roots. Spraying liquid nutrients on leaves will give miraculous results. Add half teaspoon of NPK in the ratio 1:2:3 in one litre of water. Mix well till it dissolves and spray on leaves during plant’s crucial growth stage and blooming time.
NPK can be added to the soil but be careful not to add more than a teaspoon of NPK in 10 inches pot. Dig the soil on the sides not affecting the roots and sprinkle the mixture, nowhere close to the roots. Water abundantly.
Maintain ideal pH of soil
To maintain the ideal pH level, add organic manure/compost to the soil. Nothing works better than this.
Less leaves and vigorous deep-coloured flowers are promised if annuals are provided proper sunlight, needful watering and adequate nutrients. For instance, if you find the annuals have grown lots of leaves but aren’t pushing out many blooms, try adding fertilizer with higher Phosphorous to boost flower production but lower Nitrogen, which stimulates leaf growth.
The thumb rule is to always add fertilizer in less quantity.