Well this year I am focusing more on soil preparation for the Garden. Which means i have been checking what is the best conditions for the various veg i plan to grow. I think I'm lucky with the soil i have in that i have raised bed with bought in soil on top of sand which sits on clay. Even so i want to keep my beds in tip top shape. So i have come across the dreaded N-P-K numbers on just about everything i look at. From fertiliser to manure. And I must admit its just a little confusing. So far I have been using the veg type fertilisers and manure that are specified on the packs. Now i have researched online but typically the info isn't that helpful. and would love the input of the GardenStew crowd on what info think is relevant and what isn't when it comes to fertiliser numbers. This is what i have come across so far. (please correct me) N-P-K N= nitrogen, specifically for mainly used by plants for chlorophyll, so very useful when they are growing. However to much can result in the plant growing to fast and too leafy. Good for starting seedlings P=Phosphorus typically used for setting roots and seeting seeds (fruit) So again good for seedlings but more so for plants that are going to fruit. Important when veg start to form. K= Potassium - is good for general health of plants. OK so that's what the numbers refer to 10-10-10 What the numbers refer to Now i read somewhere that the numbers refer to the parts that make up the mix, After looking at my various fertilisers this is wrong. They refer to the percentage of that chemical in the mix. For example Bonemeal is normally 2-12-0 so 12% Phosphorus which is why bonemeal is so good for root growth. This is where I am kicking myself from the weekend, and wish I understood this better. When i was looking at the multitiude of bags of both manure and fertiliser this weekend I was trying to find the best deal. Unfortunately with hindsight Price alone isn't the best way of measuring best deal. For example if a bag of 4-4-2 fertiliser is for sale for $5 and 8-8-4 is for sale at $7 the second one is the better deal as you get twice the chemicals, typically meaning it should last twice as long. Next time i go Shopping I will be keeping the % in mind. Finally whats the best ratio for veg. Typically most people suggest double nitrogen to the others so 20-10-10. Although I would imagine later in the year when the veg start to produce a more balanced percentage is better. Would love to hear from you guys on what you suggest for fertiliser ratios Thanks for any help you guys can provide on the topic.
Dan, the three numbers represent nitrogen, phosphorus and potassium respectively,which you already know. the numbers represent the percentage of each in the mix., the remainder is inert or filler material. Nitrogen = responsible for the dark green rapid growth. crops grown for their foliage need more than crops grown for a fruit or root crop. Phosphorus = root growth and of every plant. it helps to develop strong stems/sturdiness. also helps produce healthy flowers and fruit. Potassium = necessary for new cell growth, especially the roots and buds. provides the balance between the growth factor of nitrogen and the ripening influence of the phosphorus.Root crops need and use more than leaf crops. Crops also have different needs for each nutrient at different times of the plants/crops life. 4-10-40 is used when fruit is almost ripe to create more sugar in the fruit. 9-15-30 is generally used on vegetable crops in the ripening stage. 11-41-8 is used to promote blooms and enhances flowering to produce more vegetables. 20-20-20 is greenhouse grade for bedding plants. It would be helpful to do a soil analysis to see what your garden specifically needs. There is no point in giving it a nutrient it has plenty of. I hope this helps clear up some of the confusion or question of what it all means.
Thanks Carolyn that's really useful. Especially which to use at which time and the purpose of the chemicals
Hello.... Fertilizers are tricky to say the the least. I posted an article in this forum in this section titled "seed starting/ plant care" it was posted on may 11th. I'm not sure if it will help but it does explain a few key points. I grew up on a farm with many varieties of trees and vegetable crops. My father passed his green thumb to me. Take a look it might help! Enjoy the out doors and don't be afraid to experiment with different combinations. Take a few plants and use different combinations on each one. Triall and error is a great way to understand what works best. Also make a list and tag the test plants with what is used. That way next year you have a great starting position. Have fun! RJ
