Water and fertilizer go hand in hand. The nutrients in fertilizer dissolve in water. Water carries nutrients though the plant. 75% of the plants weight is made up with water.
The root hairs absorb the water, nutrients and oxygen from the soil and carrry them up the stem to the leaves. A fraction of the water is processed and used in photosynthesis.
Large plants use much more water then small plants but there are many more variables than size that will dictate your plants water consumption. The age and size of the plant, the container size and what it is made of, soil texture and composition, the temperatures, humidity and ventilation all affect the water needs of plants.
The healthier the plant, the faster it will grow and the more water it will consume.
If you have ever seen fertilizer in the store you may have noticed a series of 3 numbers on the lable. A common one is 20-20-20. Those number represent N-P-K percentages and there are different combinations for different growth stages of plants. Getting to know these numbers and the nutrients they represent will help you not only have a show stopping garden you will be able to grow a better, healthier garden and acheive maximun results from your plants.
Nitrogen (N) is the most important nutrient. N is essential to the production of chlorophyll and is mainly responsible for leaf and stem growth as well as overall size and vigor.
Phosphorus (P) is necessary for photosynthesis. P is associated with overall vigor. Plants use high levels of P during the germination, seeding and flowering stages of growth.
Potassium or potash (K) increases chlorophyll in the foliage and helps plants make better use of light and air. Potash encourages strong root growth and is associated with disease resistance and water intake. K is necessary during all stages of growth.
The goal of fertilizing is to supply the plant with proper amounts if nutrients for vigorous growth.
A plant has different fertilizer needs as its metabolism changes throughout its life. During germination and seedling growth intake of phosphorus (P) is high. The vegetative growth stage requires high amounts of nitrogen (N) for green leaf growth. P and K are also necessary on substantial levels (a general purpose N-P-K 20-20-20) is recommended. In the flowering stages P intake is highest (10-60-10) will promote larger flower growth.
Fertilizers may be either water soluble or gradual release. Both soluble and gradual release fertilizers can be organic or chemical.
Soluble fertilizers lend themselves to indoor container cultivation. They disolve in water and may be added or washed (leached) out of the soil easily. It is easy to control the exact amount if nutrients available to plant in soluble form.
Type N P K Availability
Bat Guano 5 8 .2 rapid
Blood Meal 13 1 0 rapid
Bone Meal 2 14 0 medium
Cow Manure 2 .5 1.5 medium
Kelp .3 .2 .5 rapid
Sea Guano 15 5 .3 rapid
Wood Ash 0 3 5 slow
Worm Castings 3.5 1 1 rapid
The above figures are only approximates. Please do refer to products for exact nutrient content.
There are also different fish fertilizers, compost teas and compost itself which I will write about in a future post. I am a strong believer in composting and is an excellent practice every gardener should get involved in.