920 Samoa Blvd, Ste 217, Eureka, CA 95501
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Most frequent questions and answers

The objective of soil testing is to create a soil environment that allows plants to grow their best. Proper soil nutrition ultimately leads to more beautiful and productive plants with a reduced need for fertilizers and pesticides. A soil test will allow you to eliminate guess work the goes into fertilizing, select more appropriate plants, and identify potential problem areas. Over-fertilization (even with organic fertilizers) can contribute to nutrient pollution in our our rivers, lakes, and ocean. Under fertilization will cause plants to grow more slowly and be more prone to diseases and pests.

The best time to sample your soil is before you begin your garden design, 4 to 6 weeks before installing your landscape or garden, Pre and/or post amending for the season. The relative cost of a soil test is small when you consider how much you will spend at the nursery to obtain your plants and soil amendments as well as the time it takes to maintain your plants.

Visual symptoms can be difficult to identify. Most symptoms consist of Chlorosis (yellowing of the leaf or plant), Necrosis (death of the leaf or plant). Different variations of chlorosis exist like, mottled splotchy appearance, yellowing from the inside out or the outside in, and yellowing from the top-to-bottom or bottom-to-top of the plant. Many plants will exhibit BOTH a deficiency and a toxicity at the same time. When you get a laboratory test, you can ask your plant exactly what it needs without guessing and “shooting from the hip”.

We have an entire page on this, but the tl;dr of it is: Leach Sodium – Excessive Sodium, and other soluble salts, can drive up the pH. Leaching, or washing, out the salts will bring the pH back in to range.

           Certain types of sulfur: Elemental Sulfur (S°), Iron Sulfate (FeSO4), Aluminum Sulfate (AlSO4) are different sulfur agents that lower your pH by converting to Sulfuric Acid (H2SO4) in the soil. 

Nope, that’s a ‘chemotype’ test, not an ‘Ag test’. If you’d like to test your cannabis for potency, we recommend our local lab friends at North Coast Labs, located on West End Road in Arcata.

Please don’t hesitate to write us with any other questions about our testing and services.

We do soil, plant tissue, and water testing for agricultural purposes. You can drop off your samples at our lab directly, or use one of our drop-off locations. Note: If you use a drop-off location, we are not responsible for delays in receiving samples. The turnaround time will begin when the sample enters our lab, not when your sample is taken to a drop-off location.

You can find sampling instructions at on our Sampling Instruction page. Your test is only as good as your sample.

The turnaround time for soil and water nutrient tests is 5 business days. Samples can be Rushed for a 3 day turnaround time, with a 70% rush sample fee.

DBS has partnered with Northcoast Horticulture Supply and Humboldt Ag Supply to better provide the Humboldt County farmer with everything they need from seed to sale, with the exceptions of genetics and sunshine.

You can now get your soil tested at DBS, who will create a custom Nutrient Management Plan based on your land and your crops. We can then take that to Humboldt Ag Supply to create the custom blend of soil and amendments needed to bring your soil quality up to get high production yields, every year.

And because we are all under one roof, you can get your Farm-Direct Pricing on the whole kit and caboodle. 

We love to hear from our customers! If you have a question that you can’t find the answer to on our website, please feel free to contact us using the button below and ask any question you might have. After we answer it, we throw it on this page so others can also know! 

How can I use leftover NMP material ? How should I not use leftover NMP material?

The amendments have higher nitrogen and phos concentrations than the tea food. It is my recommendation to use the leftover material as a “feed extract” rather than a “tea brew” or “tea extract”

It is not advisable to mix fertilizer with tea as they have two different purposes and the microbes are sensitive to fertilizers. DBS recommends not making teas with manures and fertilizers. We are feeding the soil with “microbes” not “NPK” We should really keep them separate.

He can extract the material and water it on to feed his plants or he can just do a top dress with it mid veg and water it in.

I understand people want to combine steps and use up extra material and that people will do what they will. Point is that I can not in good conscience recommend the practice of using the left over material in teas. That said, people do it all the time, but their tea is probably not very high quality as it pertains to microbial diversity.

It WILL NOT HURT ANYTHING so I say go for it if you want, but the above recommendation still applies.

How does DBS calculate the CA:MG ratio

We do not use the ppm to calculate it. We use milliequivalents to calculate ca:mg ratio and also the exchangeable ratio portion of our reports. Also, in context of soil science and CEC. meq/100 g of soil is just a simple conversion from cmolc/kg (traditional CEC units)

This unit takes into consideration electrical charge and atomic weight which tells us very different things than ppm….like how much will it take to replace one cation by another cation on an exchange site….or how numerous the ions of nutrients of concern are in solution- what their ratio is impacts plant nutrient uptake. The plant won’t be able to “find” calcium cations of its flooded out with magnesium ions. That is a very over simplified explanation but i hope gets the picture across…

What are good options for a mulching material around the base of my plants?

Rice Hulls are a go and work great. Straw is another option that works well. Worm Castings are also an option but very pricey as a mulching

Any wood products should be avoided  on top of a bed or a pot because they will end up stealing the nitrogen from the soil due to the high carbon content. Wood would be good however in between greenhouses, around pots and for any other area where the soil nitrogen will not be a concern

Learn More

How pH levels effect nutrient uptake
Raise or Lower pH in Soil
Soil Testing
Organic Vs Mineral Soil
Cannabis leaf under a microscope
How to take a Test