The plan is to broadcast potash and boron pre-sowing over the entire garden; i.e. including the north half that will be only cereal rye for the cover crop. Then, apply nitrogen as side-dressing.
Calculations for the broadcast amounts are as follows. The boron rates are based on info summarized at this site here.
- Blend in Borax into 0-0-66 at 1 lb/ac of boron. Since 9 lbs Borax contains 1 lb of Boron we would use 1/3 of 9, or 3 lbs Borax, as we have a 1/3 ac garden.
- 2019 soil test said to apply 60 lbs potash per ac. So, 1/3 ac would need 20 lbs of pure potash or 30 lbs of 0-0-66.
- Fertilizer plus borax = 30 + 3 = 33 lbs to spread over 1/3 ac. 43,560/3=14,520 SF. So, 33 lbs/14.52 KSF = 2.27 lbs/1000 sf.
- The flow control setting on the JD spreader should be set on the low side of 1.5.