@Toby: Steve Solomon says in his book to use both kind of lime because the rains in the West side of the cascades, has leached the soil in our region for millenias of the nutrients calcium, magnesium and phosphorous. Also our soils with a few exceptions are derived from rocks, we have very poor soil out here. The soils here provide low quality hay, with low nutrition so dairy farms have to truck in a lot of hay from the eastern part of Oregon. The good thing is the rain leaches the soil pretty uniform because coming pretty much all from rock unlike in the East Coast where there are many different kind of soils and so no matter where you live in the West side of the Cascades replenishing the soil is the same formula.
The same would apply to your region Toby.
He says that because calcium, magnesium and phosphorous are leached in high quantities it makes the Potassium (K) level too high. so if you use a common fertilizer you are adding too much of this nutrient. Too high level of Potassium lowers the nutritional value, including protein and vitamins. That is why the hay is low quality but the same can apply to your vegetables, wheat.....
He even says it lowers the quality of your compost. Coupled with our cool summers it also does not compost quickly enough so our compost is low in nitrogen which gets produced in hot, quick compost.
So to get high nutritious vegetables we need to avoid adding more then the minimum amount of potassium. One thing overabundance of potassium does, it bulks vegetables up, increase crop value and weight that's why they tell farmers to add lots of potassium to their fields. But it comes to the expense of nutritional value. Since the farmer does not get paid for nutrition but for bulk........it's different for us vegetable gardeners.
So our soil is deficient in everything but potassium. two of the nutrients we are really short of are calcium and magnesium ->Lime<- so fixing that deficiency is the most useful because doing that, allows the other nutrients to be available to the plants.
Agricultural Lime is calcium carbonate. Dolomite Lime is about 1/2 calcium carbonate and half magnesium carbonate.
If you mix together more of less equal parts of the two kinds of lime you get the right proportion for the calcium to magnesium.
He suggests if you start a brand new garden or one which never has been limed you should spread an equal mix of the two limes at a combined rate of 50 lbs per 1000 sqft (1 ton per acre). If you use his fertilizer formula as an ongoing amendment this one time, heavy application should suffice for as long you garden at that site.
He says aside a few islands off the mainland of British Columbia and down Klamath Mountains in Oregon, 98% of gardeners in the maritime NW are helped by this formula.
I have been using his formula for a few years and I think it is making a great difference.
If you are gardening in this area Maritime PNW, I highly recommend his book. It might be not the easiest read, I have to admit he could be a better writer, (but maybe it is just me, I just prefer the facts instead of story time) but his book has great information for us PNWesterners.
Here quickly his fertilizer recipe
4 parts seed meal (Cottonseed, canola meal, linseed, soybean meal.....)
1/2 part lime (equal mix of agricultural and dolomite)
1/2 part phosphate rock or bone meal (steamed or raw)
1/2 part kelp meal (any kind of pure seaweed meal from anywhere)
you could also use two or three parts fish meal (it has more NPK then seed meal) instead of the 4 parts seed meal, but it is more expensive that way
he recommends to use as much of that fertilizer as the plants will respond too,
So when they need nutrients to support their vegetative growth and grow fast feed them more, when they cannot grow fast - give them little.
Since the fertilizer releases its nutrients slower then chemical ones, for early spring sowings when then ground is still cold use a bit more then you might think necessary.
Since he says he does not know how fertile our gardens are he recommends about 1/4 to 1/2 cup per plant, all depends on your situation.
for raised Beds he says to rake in 1-2 gallons of his fertilizer spread atop each 100 sqft of growing area before sowing or planting.
This amount is supposed to be sufficient for adequate background nutrition for all vegetables and should be enough by itself for less demanding species, like Carrots.
It should feed your seedlings or transplants for up to 3 months, but this depends on the species your are growing and if they are doing lots of growing, feed them a bit more by side dressing. for a 4 foot wide raised bed side dress a small handful between each pair of 4 foot long rows. High feeders might need a side dressing every 4 weeks or 6 weeks.
I keep my ingredients in plastic trash cans and periodically mix a small bucket. Since it is in parts you can mix as much as you like and it won't spoil as long you keep it dry.
