cybersix said:
Sue - I can see the point, and I don't believe in miracles if they are on the producer page, with so few details. I read a lot of italian forums and people who's using this fertilizer see the difference, but it's quite costly for a garden. many says the same good result are obtained with a granular fertilizer called NPK gold which is a 15-9-15 with micro nutrients and magnesium too. The N in there is of two types, one is immediatley available and the other is a slow release N. Not that it costs less, it's about 1€ per Kg, but for a garden makes more sense!
Sabrina, I'm not sure if alfalfa pellets would be easily available or cost effective for you there because, unless things have changed since I lived in Europe, it is not as widely grown there as it is in North America. I don't know what the Italian name for it is but another alternative name in some countries is lucerne.
Re the fertilizer, the one you are using also has fast and slower release forms of nitrogen based on the numbers you gave. When people give comparison opinions and see a difference it depends on what they were fertilizing with before, or if they were fertilizing at all. It also makes a difference whether the plant is in soilless media in a pot or in the ground. In the ground the nutrients are naturally all there, otherwise the ground would be bare of vegetation. What can happen is that some nutrients aren't there in sufficient amounts for the optimum growth that we might want in a plant, or we might have planted something not suited to the nutrient balance or the soil pH. So we have to make additions or adjustments.
The only nutrient that doesn't come naturally from soil particles is nitrogen, which relies on microorganisms capturing it from the atmosphere (or fertilizer!). In soilless potting mixes it depends what is in the mix. Some media ingredients have very little or almost no nutrients naturally so we have to add them all, including micros. That's where you may see a significant difference between fertilizers.
If you're fertilizing in the ground you may only need NPK, or maybe even just N and K, or just N. You may or may not need to add micros but you probably should to soilless media in a pot. The same with calcium and magnesium. In your case with your high calcium soil/water you would not need to add calcium (usually done with lime) and may not need to add magnesium to your garden soil.
So there's nothing wrong with your fertilizer as far as I can see, and there's no reason (without seeing the ingredients or a test) that the NPK gold wouldn't work as well. There's no benefit in going higher with nutrients that are in adequate supply, in fact it can be detrimental. In the garden often all that it takes to make the micronutrients that are already there available to the plants is to lower the soil pH. In that case you wouldn't need to include micronutrients in the fertilizer.
I think this is getting too long so I will stop now
I don't think there is anything wrong with your fertilizer. You may be able to find something that works as well for you but is less expensive for the garden, where you do not need to provide all the essential nutrients because they're already there. In a pot you do need to provide all the nutrients so you are more likely to need something like the one you are using.
