Yemineni: Fourteen Years Building Fertigation Controls for Indian Polyhouses

In a polyhouse, somebody mixes the nutrient solution twice a day. A scoop of this, a measured pour of that, stirred into a drum and sent down the lines.

Put a meter in that drum on Monday and again on Thursday and the readings will not match. The salt concentration drifts because the scoop is not a scale, because one bag is caked and the next is not, because the person mixing on Thursday is not the person who mixed on Monday. The plants register the difference well before anyone reads it on a meter.

Yemineni, a small firm in Bengaluru, has spent fourteen years building the machines that take that job away from the drum. It makes fertigation controllers, greenhouse climate systems and hydroponic controls, and it has been at it since 2012 — long enough to matter in a segment where most of the equipment in Indian polyhouses still arrives from somewhere else.

Yemineni works out of Jalahalli West in north Bengaluru. Its own published profile puts it at fewer than ten people and an annual turnover in the ₹5–10 crore band — a workshop rather than a factory floor, which for control equipment is closer to the norm than the exception.

The specialism is narrow and has not wandered: getting water and nutrient to a plant in the right amount, at the right strength, without a person standing there doing it. Everything the company sells is a version of that problem — fertigation and irrigation control, greenhouse climate control, hydroponic controllers, and the water treatment and filtration that has to sit upstream of all of it.

Its stated customers are growers around Bengaluru and Mysore, which is the belt where protected cultivation in Karnataka is densest, and it frames its own pitch around using less water and less fertiliser rather than around yield alone.

The flagship is Fertipro, sold as an automatic fertigation and climate control system.

Concentrated stock solutions sit in separate tanks — nitrogen in one, potassium in another, acid in a third. When an irrigation starts, dosing pumps draw a small measured amount from each into the main line. A probe in that line reads the result and reports two numbers.

EC — electrical conductivity — is how much dissolved salt the water is carrying, which stands in for how strong the feed is. pH is how acidic it is, which decides whether the nutrients are in a form a root can actually take up. Get the pH wrong and iron and phosphorus lock up in the water even though you paid for them and they are sitting right there.

The controller compares both against the target you set and adjusts the pumps until they match. That loop is the whole product. Everything else is arranged around it.

The company says the controller stores 15 to 20 programmes, so a separate recipe can be held for each crop and each growth stage and called up when the crop moves on; that it runs from a touchscreen panel with a mobile app for remote access; and that it keeps a full history of what was applied, viewable as graphs.

Those four crops are not a random selection. They are what protected cultivation in India grows when the economics work: high value per square metre, sold into a market that pays for consistency, and grown under cover where a control system has something to control.

Greenhouse climate control. A station on the structure reads temperature, humidity, rainfall and wind, and those readings drive the vents, the fogging and the fans. The gain is not that a machine can open a vent — a person can open a vent. It is that the decision gets made against a measurement rather than against how the polyhouse felt to somebody at two in the afternoon, and that it gets made at three in the morning when nobody is there. Wind matters more than new growers expect: a vent left open in a gust is how polyhouse film tears, and the repair costs more than the crop it was protecting.

Hydroponic controllers for NFT and deep-water culture, where there is no soil to buffer a mistake and the nutrient solution is the growing medium. Dosing accuracy stops being a refinement and becomes the whole crop.

Water treatment — reverse osmosis and softeners — because hard or saline source water changes what a dosing system has to do, and no controller can fix water it was never given a chance to correct.

Filtration and valve control, including auto-backwash filters. Unglamorous, and the reason installations survive: a blocked dripper is the most common failure in any drip system, automated or not.

Public marketplace listings put the company's fertigation control units at about ₹2.9 lakh for the automatic fertigation control system and ₹3.95 lakh for the larger fertigation-irrigation unit. An installed system costs more and is site-specific — blocks, tanks, filtration, pipework and sensors are not in a listing price.

What that buys, in the order growers tend to notice it:

Fertiliser that stops leaving in the drainage. Hand mixing errs generous, because running short is the visible mistake and overfeeding is not. Dosing to a measured EC ends the habit, and at current fertiliser prices that is usually the first line to move.

A more even crop. Every plant on the block gets the same feed, so it matures together and more of it makes the top grade. For anyone selling tomatoes or capsicum into a graded market, the grade-out is the price.

One person covering more ground. Mixing and valve-turning stop being jobs. Across several blocks that is the difference between one supervisor and three.

A record of what was actually done. Every irrigation and dose is logged — which matters when a buyer asks, when a residue question comes up, or when one block does unexpectedly well and you want to know why. A notebook in a shed does not do this.

The sum only works on protected, high-value cropping. On an acre of polyhouse capsicum or strawberry, where the gross runs to lakhs and grade-out sets the price, a system that lifts uniformity and trims fertiliser has something to recover its cost from. On open-field cereal it has almost nothing to work with.

Fertigation and climate control arrived in India as imported kit, largely Israeli and Dutch, and much of what sits in Indian polyhouses still does. Imported equipment is generally good. What it is not is reachable in the third week of a flowering flush when a dosing pump fails.

That is the argument for a domestic maker, and it has nothing to do with patriotism. A controller built in Bengaluru by a firm that will answer the phone, holds spares in the country and can put somebody on a bus is worth more in a working season than a better specification that ships from Europe. It is the same calculation that decides whether any farm machine was a sound purchase, from a fertigation skid down to a power weeder: not what it does on the day it is installed, but who comes when it stops.

A fourteen-year track record is the part that carries weight here. Control equipment is easy to enter and hard to stay in, and a supplier still trading in year fourteen is a supplier likely to be reachable in year four of your installation.

This applies to any supplier, Yemineni included. The touchscreen is the part that gets demonstrated; the probes decide whether you are still using the system in year four.

EC and pH probes drift, and pH probes wear out. They need calibrating on a schedule and replacing periodically, and a system dosing against an uncalibrated probe is worse than no system, because it is confidently wrong. Ask what calibration involves, how often, what a replacement costs and who stocks it.

Ask what happens when the controller stops. There should be a manual bypass that lets you irrigate while it is repaired. A farm that cannot water without a working circuit board is one power surge from losing a crop.

Ask about your water first. A source-water test decides whether treatment is needed ahead of the dosing skid, and changes the quotation.

Ask to visit a working installation of similar size, without the salesperson. A grower two years in will tell you in ten minutes what a demonstration cannot.

On subsidy: micro-irrigation and protected-cultivation support runs through state horticulture departments, and automation is sometimes admissible inside a protected-cultivation package rather than on its own. Rates and ceilings differ by state and by category of holding, so the only reliable answer is the one your district horticulture officer gives you in writing.

Yemineni lists its address as Jalahalli West, Bengaluru, and publishes a phone number and email on its site for enquiries.