Kratky Kit Cost: What You Pay Upfront and Per Crop

A Kratky kit is one of the cheapest ways to grow food indoors, because it has no pump and needs no power. What it costs depends mostly on whether you buy a boxed kit or build one, and whether you add a grow light. This post breaks the cost into parts so you can price your own setup.

The three parts of the cost

Where the money goes in a Kratky kit

Part	What it covers	How often
Hardware	Container, lid, net pots, sleeve or cover	Once; reusable for years
Consumables	Hydroponic nutrient, grow media, seeds, pH test supplies	Every crop (nutrient and seeds) or every few crops
Light (optional)	An LED grow light and timer, plus electricity	Light once; electricity while it runs

Prices change and vary by store, so check current listings. The pattern below holds regardless of exact prices.

Boxed kit vs DIY

A boxed kit bundles the container, net pots, media, nutrient and often seeds. You pay for convenience and matched parts. Kits with a built-in light cost more.

A DIY kit uses things you may already have: a mason jar, a storage tote or a food-safe bucket. You buy net pots or a net pot lid, a bag of rockwool or clay pebbles, and a bottle of hydroponic nutrient. Because nutrient bottles and media bags hold enough for many crops, the first DIY kit costs the most and later ones cost very little. The article on building a DIY Kratky kit from a mason jar lists the parts.

Running cost per crop

• Nutrient: a small amount per gallon of solution. One bottle usually lasts many crops, so the cost per crop is small.
• Grow media: rockwool plugs are used once; clay pebbles can be cleaned and reused. See rockwool vs clay pebbles.
• Seeds: one packet plants many crops.
• Water: a gallon or so per plant, depending on size.
• pH supplies: strips or drops last a long time; a pH pen needs calibration solution now and then.

What a grow light adds

A grow light is the only part of a Kratky setup that uses electricity, and the cost is easy to work out from the light's wattage:

Example: electricity used by an LED grow light

Light	Hours a day	Energy per day	Energy per 30 days
10 W	14	0.14 kWh	4.2 kWh
20 W	14	0.28 kWh	8.4 kWh
40 W	14	0.56 kWh	16.8 kWh

Multiply the monthly kWh by your electricity rate to get the cost. For example, 8.4 kWh at a rate of 15 cents per kWh is about $1.26 a month. A window costs nothing, so a kit on a bright sill has no running energy cost at all. The Kratky grow lights guide covers how much light plants need.

Where people overspend

• Air pumps and air stones. Not needed for Kratky. Adding them makes it deep water culture. See Kratky vs DWC.
• Several nutrient lines for a single jar. One complete hydroponic nutrient is enough for leafy greens and herbs.
• Meters before they are needed. pH strips are fine to start; an EC or TDS meter is useful once you grow more than a jar or two.
• Clear containers that then need covers to stop algae.

The Kratky supplies checklist separates the essentials from the extras.

Does it save money on herbs and greens?

Whether a kit saves money depends on what you grow and what you would otherwise buy. Herbs such as basil, which are often bought in small packs and go to waste, are where a kit tends to pay off fastest, because you pick only what you need. Lettuce grown cut-and-come-again gives several harvests from one plant. A kit used for many crops spreads the hardware cost thin.

For help picking a kit, see the guide on how to choose a Kratky kit or the Kratky hydroponics kit home page.

Frequently asked questions