Fast in appropriate soil temps. Persistence depends upon how fast the N volatilizes, leaches, and adsorbs which are chemical reactions mitigated by temp, moisture, and biotic activity.

Dan

The Nitrogen in blood meal is highly soluble, very readily available, very fast acting and it immproperly applied can easily burn plants.
When did you take that soil test? Most of the home test kits I have experience with will show a low N in cold soils which would be normal since the soil bacteria would not be active to make it available to the plants.

The last time was in August this year. So no cold soil yet.

Home soil test kits do not accurately measure nitrogen levels. In fact, a great many professional labs do not measure nitrogen or require special testing procedures to measure it because of its volatility. You can have radically different levels in different parts of your garden as well as levels that change through the course of the day, at least during the primary growing season. In general, unless you routinely apply organic matter, nitrogen will tend to be deficient in your soils because of its very transient nature.

As far as organic inputs are concerned, blood meal is considered very fast acting. As noted above, it is highly soluble, which is unusual for an organic fertilizer. You would want to use it only according to label directions, as it can easily 'burn' roots and plant tissue if over applied.

Here is a link that might be useful: understanding nitrogen in the soil

FWIW - you should not use bloodmeal or have it in the soil at any significant level when soil temperatures are below 55* because of the danger of ammonium toxicity, a malady often witnessed by hobbyists, but seldom accurately diagnosed. Additionally, you should avoid it's use if you suspect the soil will be soggy or it's compacted and if pH levels are low.

Most people that THINK they need a fast acting charge of N would be better served if they rethought that plan.

Al

I think it would be best if the term, "fast acting" was not used when it comes to plant nutrients. Availability is a far better way to refer to nutrients whether they are in the soil already or being applied from any source. Fast acting is probably just an advertising term.

Michael

I had a s/a response all ready to post, but I was good, and decided to forgo posting it.

Al

I'm going to disagree :-) "Fast acting" is very common, even accepted, terminology when it comes to fertilizers. And there is a difference between nutrients and fertilizers. Nutrients are the base ingredients, a variety of 18 or so chemical elements necessary for plant growth and health - fertilizers are merely the delivery vehicles.

Plants access nutrients only in the form of soluble ions. Synthetic fertilizers tend to present nutrients in highly soluble forms, therefore the nutrients are readily, even immediately available. Immediately or readily available = fast acting. That's why they coat or prill various synthetic ferts to control or slow down the release of nutrients over a period of time. Most organically sourced fertilizers are insoluble and require the activities of soil organisms to convert them into the soluble ions the plant roots can access. And that takes time and is also influenced by climate, soil moisture and soil temperatures as well. That's why most organic ferts are considered naturally 'slow release'.

I would suggest using alfalfa pellets for nitrogen. They also contain other minerals which will help your soil. Bonemeal attracts varmints which may dig up the plants/garden looking for "bones".