When people visit the farm and ask what I've done to the pastures, when I mention lime, it sort of goes in one ear and out the other. Our soil is (was) very acidic and not just on the surface. Nearly all of our sub-soil has (hopefully had as in past tense) a pH <4.3 in CaCl2. It's imperative I fix this ASAP otherwise the pastures will not grow and carry the numbers I'm aiming for.
We have applied 4-5t/ha of high quality lime, with the 3.1pH area receiving 12t/ha and it recently received another 5 t/ha. It's made a huge difference to the pasture growth. Nothing would grow before on that area except reeds, tea trees and bracken.
In my experience, it will take at least two years in this area for the pH to improve where I can expect to achieve ~80% of pasture growth that is possible. I must admit, the pastures are growing faster than I thought they would and we still have another 2+ months of spring to come - October is our peak pasture growing month. This wouldn't be possible if I had only put on 1T/ha of a high quality lime, let alone a low quality lime.
It cost us ~$62/t landed for the lime, so it was a huge input. But it was an essential input. If I didn't fix the problem, the pasture would not be able to respond like it is in the photos below. These photos were taken yesterday, Saturday 31st August 2019.
The order of importance to fix is: pH (if too low), trace elements, P, S, K & Mg (if needed), and N is last. As I push the pasture production, weaker areas show up more clearly and then as I fix those, the next weakness becomes apparent. It's like a ladder. Sometimes you slip and run out of a nutrient so you add that to climb back up and then another nutrient causes you to slip a rung, so you fix that and so on. As an example, I have some low manganese spots appearing, and this afternoon I noticed some low sulphur areas that were not present until I had applied fairly high doses of other nutrients.
It's a constant learning process of correcting problems but only feeding the pastures when you need the feed. There is no point in throwing fertilisers at the pastures if you don't have the animals to convert it (eat it). Sometimes the pastures grow more than you need, and other times the animals get on top. If you have the moisture, it's cheaper to feed the pastures than feed the animals.
It is amazing what pastures can produce if there are no nutrition limitations. In about three years from now, I hope I can have an accurate estimate on what the top end possibilities are on this first farm. It will be higher than I expect!
For those who don't know, we won't be cutting any hay or silage. It is more profitable for us to carry more sheep and buy in some roughage. We'll be over 5,900 sheep on the 185ha by this coming week if the 2,000 trade sheep arrive. Our first weaned lambs head off for their eternal holiday tomorrow, so another milestone coming up for us.
