I’d be very cautious of using blood personally only thing I’d use blood on would be in the compost pile used to get it activated really quickly what ya got with compost and manure( aged ) should work a 'tid bit from Motherearth news
Iron
Next up is iron. The trace element plays major roles in the production of chlorophyll and in the nitrogen-fixation process. It also helps reduce nitrates to ammonia for the synthesis of plant proteins.
Chlorosis is a primary symptom of an iron shortage, but it’s not a reliable indicator without a soil test because yellowing indicates other nutrient deficiencies as well. Additional symptoms include new shoots that stop growing, and in severe cases, top growth dies. Fruit-tree leaves turn yellow and develop brown areas, and fruits generally
lack flavor. Excessive lime and/or phosphate may inhibit a plant’s intake of copper, so apply small amounts when copper or other trace-element deficiencies exist.
Chelation is a process that makes iron available to plants. In short, iron in an insoluble form is attracted to organic chelates that plants readily absorb. When plants absorb chelates, they also take in the captured iron.
The best way to put iron and chelates into the soil is by the addition of organic matter. Manures (especially chicken manure), garden and kitchen wastes, greensand, dried blood, and/or seaweed added to the compost pile provide all of the iron that plants need.