Posted: 16/05/2014 at 09:01
BleuFairy, I'm Australian originally, been here 9 years.
You could use a 20:20:20. The point is that it's balanced. I've only ever found a 10:10:10 here once. One of the problems for the domestic gardener here is that there isn't a "garden centre" culture per se. Specialised agricultural supply outlets are still mainly targeted at farmers. It can be very frustrating.
For liquid fertilisers, only worry about the NPK.
Humus-rich just means plenty of organic material - garden compost, leaf mould, aged (not fresh) horse manure, etc. Apart from giving the plant roots a good healthy environment from the start, organic material drains very well.
A soil pH of 5 or 6 is acid. 7 is about neutral, and the higher the number, the more alkaline the soil. As I said, Italian soil is naturally alkaline. The Italian peninsula is basically a big lump of limestone. The water is naturally very alkaline too. Look at the build-up of lime in your jug or kettle.
In fact, it gives me problems with my tomatoes. Toms like slightly acid soil. When I plant out the toms, I mix some acid potting mix into the hole to counter the alkaline soil. Then, when watering, to counter the very alkaline water, I add a tbsp of vinegar to a gallon of water every second or third time I water.
Terriccio is what they call the soil/potting mix in bags. Avoid the cheap supermarket or Brico stuff like the plague. As always, you get what you pay for. I've used Compo, it's very good. Stick with it.
Torba means peat. Terriccio is just about always peat-based. The pH is listed on the bag more often than not. But, if not, you can be sure the terriccio is on the acid side of neutral because peat is naturally acidic. However! Because the soil you add the terriccio to is naturally alkaline, and because you'll be adding alkalinity every time you water, the acid nature of the terriccio won't be a big problem.
The plants need to be well-drained. What sort of soil do you have in its natural state? Clay-based? Sandy? Loam? Knowing what you have to start with will dictate what you have to do to it. If you're not sure, the best bet is to dig a hole, fill it with water, and watch what happens. If the water sits in the hole, you're clay-based. If it drains straight away, it's sandy. If it gradually drains away, you've got loam.
As to the fertilising, you can mix in some pelleted horse or chook manure when planting. Just keep it away from the roots. A high phosphorus fertiliser is one where the P figure is substantially higher than the N or K. Phosphorus assists flower development.