Can nutrients be used with Blumat Systems?
The answer to this question is rich with subtleties and nuance, which is why it needs to be addressed with an article as opposed to a yes/no. The short answer is generally yes, with some caveats.
The devil’s in the details, and whether any given regimen is compatible with a Blumat Watering System is dependent on many factors.
Factors Influencing Blumat-Compatibility
Dosing Volume & Frequency
These are the most obvious and immediate factors that will determine how problematic any given fertigation program is compatible with a Blumat Watering System.
The concentration of nutrients (dose) as well as frequency of nutrient application are the first and foremost factors impacting how compatible a nutrient program will be with a Blumat Watering System. When converting from a drain-to-waste style, we recommend using 25-50% dilution rates of nutrient concentrations.
The thicker the nutrient solution, the more likely it is to clog a system or cause other issues.
Organic vs. Synthetic
Organic nutrients are generally stickier, more encouraging of biological growth, and mix into higher-viscosity solutions. These are generalities, and your specific organic fertilizer/additive may not fit the description.
However, if these generalizations apply to your organic fertilizer, it is more likely to clog your system than a lower viscosity and more sterile synthetic fertilizer/additive.
Broadly speaking, synthetic fertilizers are less likely to cause problems in a Blumat System.
Water-Soluble vs. Particulate
The more water-soluble a nutrient or additive is, the more likely it is to be successful in a Blumat Watering System.
When an additive or nutrient has physical particulates that “settle out” in a reservoir or solution, it poses a higher risk of causing problems in a Blumat system. Luckily, physical particulate matter can generally be filtered out prior to entering a Blumat System.
System Flow Rate/Reservoir Turn-Over Rate
Systems that have nutrient solution sitting in the tubing for extended periods of time will tend to have more problems using nutrients. The longer the solution sits stagnant in a reservoir or irrigation tubing, the more likely it is to “settle out” and have physical condensates in the tubing/res, as well as being more likely to encourage biological growth, algae, and biofilm.
Larger, commercial-scale systems with a faster turn-over time of the nutrient solution in reservoirs/irrigation tubing will reduce the likelihood of excessive nutrient build-up (and subsequent problems). These are the systems most likely to be successful with nutrients and other additives.
Strategies & Products to Mitigate Problems
Installing Flush Valves
When designing water supply for a Blumat Watering System, I always recommend incorporating flush or purge valves. In a system that is supplied by a pump and/or pressurized line, these valves be placed at the end of each water supply line (instead of an end plug).
These valves will remain closed 99% of the time the system is installed and operational. If/when air, debris, biologicals, or anything else unwanted makes its way into the supply line, the valves can be opened. The pressure of the system should force any undesirable matter out of the end of the tubing.
Once a steady, clean flow of water is achieved, the valve can be closed again to resume normal operation of the system.
In gravity-fed systems, I recommend a loop design of water supply. In this case, a Tee-fitting is installed in the mid-point of the loop at the point furthest from the reservoir (or equidistant from multiple bulkheads in the reservoir). A valve is placed on the open end of the tee fitting, and is operated the same way as in a a pressurized system–it should remain closed until the operator needs to purge or flush the lines.
Valves can even be installed on the ends of BluSoak tape lengths–these valves can be opened to purge tape of any debris in the same way.
Filters prevent physical debris, particulate, and other particles from getting into water supply tubing. Filtering does not do much to prevent biologicals and biofilms, but mitigates risk of debris, sediment, or some other physical blockage of irrigation tubing. It is one of the most simple and reliable ways of reducing clog-risk.
Disk Filters (For Commercial Systems)
When using nutrients and other additives that are not completely soluble (or tend to settle out even after becoming solubized), it is recommended to use additional products to assist in making the products as water-soluble as possible. When nutrients or other particulates settle out, it can increase risks for physical blockage (even after filtering systems/stations) as well as biofilm production.
For organic nutrients, drinking-grade Biofilm Buster is recommended to assist in solubizing nutrients and reducing risk of clog/bioflims. It is added to a reservoir at a dilution ratio of 2000:1 and is OMRI listed.
For salt-based or mineral-based nutrients, dripclean is recommended to assist in solubizing the nutrients and reducing risk of clog/biofilms.
Other Relevant Information
Guide to Automatic Dosing/Dosatron Technology & Blumat Systems
For in-depth discussion of automatic nutrient dosing and using Dosatron technology with Blumat Watering Systems, check out this article.
Switching Between Nutrients/Water
Two reservoirs can be integrated if the cultivator would like to switch between a nutrient solution and a pure water solution (or, between two different solutions). The two reservoirs should just be connected using valves and a tee fitting. The cultivator can open/close valves depending which reservoir they’d like to draw from at a given time.
- Most nutrient programs are compatible with Blumat systems, but appropriate precautions should be taken
- Distribution Drippers will clog before anything else
- Dosing/Frequency is important!
- Pre-emptive strategies like filtering, choosing water-soluble nutrients, and using nutrient-solubizing products are better than trying to clean/clear lines later
- Flush Valves pre-emptively manage nutrient-related (and air/debris-related) problems and should always be incorporated into a design
- The faster the “turn-over” of a reservoir, the more likely nutrient-use will be successful