Soil Connectivity – Why, How and using the results

Hi All,

I need more info on the hows and whys of soil connectivity tests.

My understanding, that by taking a reading using an EC meter and recording the reading.
One can determine the minerals available in the soil and monitor the nutrient availability throughout the growing season.

I have not determined what the ideal reading should be, but have read that at planting - 200 millisiemens and 600 to 800 millisiemens when the plant is in a growing phase.

The process is to have a reading before planting (Is it worth planting the crop at all?) and then monitoring throughout the growing phase.

By taking regular readings one can see if there are any nutrient deficiencies that need to be addressed as this does not show up in the leaves till it may be too late.

I know that if you feed your crop regular, this should not happen but for a little effort and hardly any cost it may be well worth it.

All input on this subject will be helpful.

Thanks in advance
Anthony

Lets look at what you are asking here. EC = Electrical Conductivity  Not minerals but salts create soil EC readings.
High EC meter readings tell you that this soil has a lot of salts in it, and that adjustment might be needed.
It does not tell you which mineral salts are present, just that salt levels are either high or low or pretty good.

The use of an EC meter should be accompanied by other tests, and by the way a good EC meter is going to set you back 200+ dollars for the apparatus then you need calibration solutions to set it up each time you are going to use it.

Taking regular readings will give you a salinity profile curve, what this tells you is increases and decreases in salinity of that soil.
What an EC meter can suggest is the level of anion/ cation exchange in the soil being tested. This tells you a little about the plant growth ability the soil supports.

Unless you are prepared to invest in either lots of tests run by labs or building and learning how to use your own laboratory, I wouldn't waste the money on a meter.
I would invest that money in full soil tests run by a certified lab instead. Those results will give you a mountain of data and information to use, instead of a single parameter.

Redhawk

Hi Redhawk,
Thanks for the answer.
Can you please tell me what the readings constitute such as
Low/Bad – Med/Average – High/Good
I would like to better understand EC meter readings.
Cheers
Anthony

hau Anthony,  Sadly, there is not really an easy answer to what readings are good vrs. bad.
That is because each type of soil function has a different EC level for best operation of the function.

Tomatoes grow best at an EC of 1.8 but beans grow best at a 2.2 reading (both calculated), however, this is just one aspect of soil function.
Soil does so many things, that growing plants is not the most important role soil occupies in our world.

The link below is to the NRCS EC pages for educators, it will give you lots to think about and it is great knowledge to have in your tool kit.
NCRS soil EC

Redhawk

From my Notes: {BTW this is for non-conventional farmed property, if NPK is your jam then this isn't the best approach for you}
Summary of Dan Kittredge’s approach to soil EC (electrical conductivity) management, incorporating the specific details about clay, organic matter (OM), and practical application using an EC meter:

Optimal EC Ranges:

Baseline Start: 150 µS/cm (0.15 dS/m) – starting point for the season. Adjustments below for OM
Target Peak: 350–850 µS/cm (0.35–0.85 dS/m) – ideal range during peak growth.

350 µS/cm (0.35 dS/m): Awesome end-of-season target for soils with 10% OM.
850 µS/cm (0.85 dS/m): Target end-of-season for soils with 1% OM.

Danger Zone: >1000 µS/cm (1 dS/m) – risks salinity stress, potentially frying roots (e.g., salt at 2000 µS/cm = severe damage).

Clay Soils: Naturally higher EC (up to 8000 µS/cm or 8 dS/m) due to ion retention.
Organic Matter Influence: Higher OM (e.g., 10%) lowers EC readings by improving soil structure and buffering salts; low OM (e.g., 1%) results in higher EC.

EC Meter Protocol:
Tool: EC meter get WITH probe or you waste time.
Frequency: Use weekly for 1 hour, measuring “everywhere” (center bed, side beds, depths of 2-4-6-8 inches, etc.).

Record: Track readings with Brix (Solids content) for correlation.

Trend: Aim for an upward EC slope over the season, reflecting increasing nutrient availability.
Managing EC. Small Adjustments.
High EC (>1000 µS/cm):
Add Humates: Slows conductivity, buffers toxicity (especially in conventional farming). Liquid humates can be used.
Carbon Source: Enhances microbial activity to stabilize soil.
Low EC (<350 µS/cm):

For 100 sq ft:
Molasses/Sugar: 0.4 tsp (0.1 tbsp) in warm water. &
Salt water: 1.8–3.7 tbsp.  

For 1000 sq ft (0.023 acres):
Molasses/Sugar: 3.7 tsp (1.2 tbsp) in warm water.
Salt water: 1.8–3.7 cups.

For 1 acre:
Molasses/Sugar: 1 qt -1 Gallon molasses or 1–5 lb sugar in warm water.
Salt water:  10 gal.

Test Small Patch: Trial before broad application.
Dry Soils: Add water to activate low EC mixtures. EC doesn't work in dry soils.
If you can't maintain Hydration you are wasting time and money.

Soil Torque: Ensure proper aeration to avoid high EC spikes.
Additional Notes
Humates: Buffer salts and toxicity, critical for maintaining balanced EC.
Moisture: Essential for accurate EC readings; dry soils show falsely low EC.
Monitor: Use EC meter alongside visual plant checks and Brix to fine-tune management.
For precise application, test small areas, measure regularly, and adjust based on OM levels and crop response.

If crops, plants, and soil are too wet for too long and appear droopy, the soil may be nutrient-depleted.
Low Electrical Conductivity (EC) readings indicate washed-out soil. Apply sea salt and sugar (molasses) to the soil to boost conductivity.  

For 100 sq ft:
Molasses/Sugar: 0.4 tsp (0.1 tbsp) in warm water. &
Salt water: 1.8–3.7 tbsp.  

For 1000 sq ft (0.023 acres):
Molasses/Sugar: 3.7 tsp (1.2 tbsp) in warm water.
Salt water: 1.8–3.7 cups.

For 1 acre:
Molasses/Sugar: 1 qt -1 Gallon molasses or 1–5 lb sugar in warm water.
Salt water:  10 gal.