Friday, April 24, 2009
Nitrogen = Sugar!
I get very frustrated with fertilizer sales people. The emphasis is always on “greening up”, “quick green” and “super green”. At the nursery we can feed hungry looking plants and see a response in just a few days, there is no miracle in this. Add nitrogen!
Commercial citrus and lawn fertilizers are often full of Nitrogen for a quick flush of green. However just like sugar this ‘hit’ is powerful but short lived and if not carefully managed it can be very bad for plants. Too much quick, lush growth can soften plants just like too many sweets soften my belly (see photo, that's my daughter Emma she did the painting).
The other concern with too much nitrogen is that most fertilizer sources supplying nitrogen have to convert it through an ammonium stage to make the nutrient available for your plants to use. Ammonium, same stuff you clean the shower with! Not great if you get too much. That’s why nurserymen talk about poultry manure and Blood & Bone being HOT.
So what do I recommend? Have a look at my list of fertilizer sources from last week. Poultry litter (as distinct from manure), sheep and cow manure are excellent materials to add directly to garden beds. The organic fertilizers with medium to high Nitrogen contents (You can add Urea as a great source of nitrogen) are best used to fire up your compost. Use the compost to give your garden a good square meal.
One thing leads to another, I had best talk about composting soon!