Growing food in an apartment sounds like it shouldn’t work. No garden, no soil, no outdoor light, and in most cases barely enough windowsill to keep a cactus alive. I thought the same thing before I set up my first hydroponic system in my spare room. That was three years ago. Since then I’ve run Kratky jars, DWC buckets, and an AeroGarden on my kitchen counter, and I’ve grown more lettuce, basil, and spinach than I can consistently eat.
This guide covers everything you need to start hydroponics at home from scratch: what the systems are, which one to start with, what to grow first, and what kills most first attempts before they get going.
What Is Hydroponics? (The Simple Version)
Hydroponics is a method of growing plants without soil. Instead of drawing nutrients from the ground, plants get everything they need through a nutrient-rich water solution delivered directly to their roots.
Plants don’t actually need soil. They need water, nutrients, oxygen, and light. Soil is one delivery mechanism for the first three. Hydroponics replaces it with a more direct one. Because plants aren’t working as hard to search for nutrients, they often grow faster and produce more than their soil-grown equivalents. A 2023 review published in the journal Bioinformation found that hydroponic lettuce production can generate up to 20 times higher yields per acre compared to soil-based cultivation.
For apartment growers, the relevant point is simpler than that: a single Kratky jar on your kitchen counter will produce more lettuce than a comparably sized pot of soil. You don’t need land, weather, or a garden to grow food.
Why Apartment Dwellers Are Switching to Hydroponics
Soil gardening requires outdoor access, seasonal timing, and a climate you can’t control. Hydroponics removes all three requirements. You can run a productive food garden year-round in a corner of a spare room or on a windowsill, regardless of season or floor space.
The water efficiency gains are real and significant. Hydroponic systems use around 90% less water than conventional soil growing because water recirculates through the system rather than draining away. The same 2023 Bioinformation review confirmed that nutrient film technique systems reduce water consumption by 70-90% through recirculation. For anyone growing inside where spilling a reservoir means water damage, that efficiency also limits the consequences of mistakes.
The home hydroponics market reflects this growing interest. Markets and Markets projects the segment will grow from $1.8 billion in 2025 to $3.77 billion by 2030, driven largely by apartment growers and people who want fresh food without outdoor space.
The practical appeal is more direct than any market figure. You plant lettuce seeds, add nutrient solution to a jar, and come back in three to four weeks with fresh salad. No digging, no weeds, no soil to buy or dispose of.
The 6 Hydroponic Systems and Which One to Start With
There are six main types of hydroponic systems. They differ in complexity, cost, and how water and nutrients reach the roots.
| System | Electricity Needed | Difficulty | Starting Cost | Best For |
|---|---|---|---|---|
| Kratky | None | Very easy | $20-$40 | Absolute beginners |
| Wick | None | Very easy | $15-$30 | Minimal investment, low maintenance |
| Deep Water Culture | Yes | Easy | $50-$100 | Beginners ready to scale up |
| NFT | Yes | Moderate | $80-$200 | Intermediate growers |
| Ebb and Flow | Yes | Moderate | $100-$300 | Varied crop types |
| Aeroponics | Yes | Advanced | $200+ | Experienced growers |
Kratky Method
A completely passive system. Plants sit in net pots above a reservoir of nutrient solution. The water level drops as the plant drinks, and the gap that forms between the water surface and the net pot provides the oxygen roots need. No pump, no electricity, no timer. The plant manages itself.
Deep Water Culture (DWC)
Plant roots are fully submerged in nutrient solution. An air pump keeps the water oxygenated. Requires electricity and slightly more equipment than Kratky, but produces faster growth and handles larger plants well. The natural second step after mastering Kratky.
Wick System
The simplest system: a wick draws nutrient solution up from a reservoir to the growing medium by capillary action. No electricity, no moving parts. Growth is slower than Kratky or DWC, but startup cost is the lowest of any system.
Nutrient Film Technique (NFT)
A thin film of nutrient solution flows continuously along a shallow channel, over the roots, and back to a reservoir. Efficient and scalable, but requires a pump, precise slope calibration, and more monitoring than passive systems.
Ebb and Flow
The growing tray floods periodically with nutrient solution, then drains back to a reservoir. More components to configure and time correctly. Good for a range of crops, but more complexity than most beginners need.
Aeroponics
Roots are suspended in air and misted with nutrient solution at regular intervals. The most oxygen-rich method, producing fast growth and high yields, but also the most technically demanding. Not a starting point.
Your First System: Start With Kratky
If you’ve never grown hydroponically before, start with Kratky. Not because it’s the most productive system (DWC grows faster), but because it removes every way a beginner can fail with equipment.
There’s no pump to fail, no timer to misconfigure, no electrical connection near water. You fill a jar, add nutrients, suspend your plant, place it under light, and leave it. Get the pH right, don’t interfere too much, and it produces food.
The failure modes in Kratky are limited: wrong pH, wrong nutrient concentration, not enough light. All three are fixable with a $15 digital pH meter and attention in the first week. Compare that to DWC, where you also need to manage dissolved oxygen levels, pump reliability, and the fact that roots die quickly if the pump stops during a power outage.
I grew lettuce in mason jars for about six months before I set up my first DWC bucket. By that point I understood pH, nutrient mixing, and what a healthy root system looks like. Upgrading made sense because I had a foundation. Starting with DWC as a first-time grower means managing too many variables at once.
For apartment living specifically, Kratky fits naturally into a normal space. A few jars on a shelf under a clip-on grow light doesn’t need to be explained to a flatmate. It looks like someone who cares about plants. A full DWC setup with an air pump, reservoir, and grow tent is a different conversation.
What to Grow in Your First Hydroponic Setup
Start with lettuce. It’s fast, low-maintenance, and forgiving of the kind of mistakes first-time growers make.
| Crop | Time to Harvest | Difficulty | Works in Kratky |
|---|---|---|---|
| Lettuce (butterhead, romaine) | 3-4 weeks | Very easy | Yes |
| Spinach | 4-5 weeks | Easy | Yes |
| Basil | 3-4 weeks | Easy | Yes |
| Kale | 5-6 weeks | Easy | Yes |
| Mint | 4-6 weeks | Very easy | Yes |
| Cilantro | 3-4 weeks | Easy | Yes |
| Strawberries | 10-12 weeks | Moderate | Yes (larger container needed) |
Lettuce has low nutrient requirements, germinates quickly, and the gap between “something went wrong” and “the plant dies” is long enough that you can diagnose and fix problems before they cost you the grow. Basil is a close second: slightly faster under good light and produces multiple harvests from one plant, but more sensitive to temperature drops.
The crops to avoid in your first grow are fruiting plants: tomatoes, peppers, cucumbers. They have higher nutrient requirements, longer growth cycles, need more light intensity, and often need pollination. Learn the system with leafy greens first. After three or four successful harvests, you’ll know whether you want to invest in the larger setup fruiting plants require.
Nutrients, pH, and Water: What You Actually Need to Know
Three things control whether your plants grow well: nutrients, pH, and water quality.
Nutrients
Hydroponic plants get everything from the nutrient solution, so it needs to contain nitrogen, phosphorus, potassium, and a range of trace minerals. For a first grow, buy a one-part all-in-one hydroponic nutrient concentrate. These are formulated to cover everything a leafy green needs in a single product, and you mix them with water according to the bottle instructions.
General Hydroponics MaxiGro is a good starting point: a dry concentrate that mixes cleanly, covers the full nutrient range, costs around $15-20 for a 2.2lb container, and lasts several growing cycles at beginner volumes. The General Hydroponics FloraSeries is a well-regarded intermediate option if you want more control, but it’s a 3-part system requiring you to mix FloraGro, FloraBloom, and FloraMicro in sequence. That’s unnecessary complexity for a first grow.
Avoid conventional garden fertilisers. They aren’t formulated to dissolve cleanly in water, and residues can affect pH and clog passive systems.
pH
This is the part most beginners skip, and it’s why most first grows fail.
pH controls whether your plant can access the nutrients in the solution. Even if you’ve added the right nutrients, the wrong pH means the plant can’t absorb them. Leafy greens and herbs grow best at a pH of 5.5 to 6.0. Below 5.0 or above 7.0, nutrient uptake slows significantly regardless of what’s in the water.
You need a digital pH meter. A basic model costs around $15-20 and is accurate enough for home growing. Buy a bottle of pH up and a bottle of pH down at the same time. Mix your nutrient solution, check the pH, adjust until it reads between 5.5 and 6.0, then fill your reservoir. Check it every two or three days, more frequently in the first week while you’re getting a feel for how your tap water and nutrients interact.
Skipping pH is the single most common reason beginner grows produce stunted, yellowing plants despite the grower doing everything else correctly. The plant looks nutrient-deficient. It’s not. The nutrients are there; the pH is blocking access to them.
Water Quality
Standard tap water works for most home hydroponic setups. Two things to account for: chlorine and starting pH.
Most municipal water contains chlorine or chloramine. Chlorine dissipates if you let tap water sit uncovered for 24-48 hours before use. Chloramine doesn’t evaporate the same way, so if your local water uses chloramine (check with your water utility), use filtered water or add a small amount of vitamin C (ascorbic acid powder) to neutralise it before mixing nutrients.
Tap water typically comes in at pH 7.0-8.0, above the range your plants need. Adjust down with pH down solution after adding nutrients, and recheck before topping up the reservoir.
How to Set Up Your First Kratky System (Step by Step)
What you’ll need:
- 1-litre mason jar (or any opaque container of similar size)
- 2-inch net pot
- Hydroton clay pebbles
- One-part hydroponic nutrient concentrate (MaxiGro or equivalent)
- Digital pH meter
- pH up and pH down solutions
- Lettuce seeds
- Cover the outside of the jar with foil or paint it to block light. A transparent jar lets light into the reservoir and causes algae growth that will take over within a week.
- Fill the jar with water to about 1cm below where the bottom of the net pot will sit when placed in the jar opening.
- Mix in nutrients according to the bottle instructions. At 1-litre scale you’re using a small amount: follow the instructions exactly, and if anything, start at the lower end of the recommended range.
- Check the pH and adjust to 5.5-6.0.
- Rinse the clay pebbles and fill the net pot.
- Plant your seed into the clay pebbles, pushing it just below the surface.
- Lower the net pot into the jar so the bottom of the pot just touches the water surface.
- Place the jar under a grow light or in a bright window receiving at least 6 hours of direct light per day. Germination typically takes 3-7 days.
Once the plant is established, the water level will drop as it drinks. This is what you want. The gap that forms provides oxygen to the roots. Top up when the level gets very low, but don’t fill it back to the starting level: maintain that air gap, or you’ll drown the roots.
Harvest outer leaves once the plant reaches a usable size, typically 3-4 weeks for most lettuce varieties. The plant will continue producing new leaves for several weeks after the first cut.
Six Beginner Mistakes That Kill First Harvests
| Mistake | What Happens | How to Avoid It |
|---|---|---|
| Skipping pH testing | Yellowing leaves, stunted growth despite correct nutrients | Check and adjust pH to 5.5-6.0 every 2-3 days |
| Using transparent containers | Algae takes over the reservoir within a week | Cover jars with foil or use opaque containers |
| Using garden fertiliser | Residues clog systems, cause pH swings | Use hydroponic-specific nutrients only |
| Insufficient light | Leggy, weak growth that produces little | Add a clip-on LED grow light for windowsills without direct sun |
| Filling the reservoir too high | Roots lack oxygen, slowing growth | Maintain a 1-2cm air gap between water and net pot bottom |
| Starting with too many plants | Hard to diagnose what went wrong | One jar, one plant, one growing cycle first |
The transparent container problem catches a lot of first-time growers. It seems logical to use a clear glass jar so you can see the water level. But light hitting the nutrient solution causes algae to bloom, and once it takes hold it clogs the system. A strip of black tape or foil wrapped around the outside of the jar costs nothing and prevents it completely.
What Does a Starter Kit Cost?
You can set up a functional Kratky system for $50-80. Here’s what that covers:
| Item | Approximate Cost |
|---|---|
| 1-litre mason jars (pack of 4) | $8-12 |
| 2-inch net pots (pack of 10) | $5-8 |
| Clay pebbles, small bag | $8-12 |
| MaxiGro nutrient concentrate (2.2lb) | $15-20 |
| Digital pH meter | $15-20 |
| pH up/down kit | $8-12 |
| Seeds | $3-5 |
| Total | $62-89 |
A clip-on LED grow light adds $20-35 if your space doesn’t get at least 6 hours of direct light per day. For most apartment windowsills, it isn’t optional. It’s what separates a plant that produces food from a plant that survives but barely grows.
Monthly ongoing costs are low after setup. Nutrients cost pennies per litre at home-growing concentrations. The main recurring cost is electricity for the grow light on a timer, which adds roughly $5-10 per month.
If you want to skip the parts-sourcing exercise entirely, a basic all-in-one starter kit from a reputable retailer bundles most of this for $60-100 and gets you growing faster. Check that any kit includes a pH meter and adjustment solutions: many don’t, and starting without pH control is one of the most reliable ways to fail.
Where to Go After Your First Harvest
Once you’ve completed a full Kratky cycle, you’ll have a clear sense of where to go next. Most growers split into two paths.
The first is to scale the same system: more jars, more plants, a small shelf with a longer LED strip above it. This stays simple, costs very little to expand, and produces a meaningful volume of fresh food with no added complexity.
The second is to move to a recirculating system. DWC grows plants faster and handles larger crops than Kratky can. Our deep water culture guide covers the setup in detail, and the comparison of beginner hydroponic systems lays out which system fits which situation depending on space, budget, and how much you want to harvest.
If you’d prefer a fully automated setup, smart garden systems like the AeroGarden combine nutrient delivery, lighting, and a growing structure in a single plug-in unit. Less hands-on learning, but faster to get producing.
For other growing options beyond hydroponics, the apartment gardening section covers what works in a small space. Microgreens in particular are worth starting alongside your Kratky setup: they need no specialised equipment, grow in 7-14 days, and produce some of the most nutrient-dense food you can grow at home.
Frequently Asked Questions
Can You Grow Hydroponically Without Electricity?
Yes. The Kratky method and wick systems require no electricity or pumps. Plants draw nutrient solution passively, making them the most apartment-friendly options. There’s no pump noise, no electrical connection near water, and no running cost beyond a grow light if your space needs one.
How Much Space Does a Hydroponic Setup Need?
A single Kratky jar takes up about the same footprint as a coffee mug. A modest setup of six to eight jars producing regular lettuce and herb harvests fits on a standard bookshelf. If you add a grow tent for light control, a 60 x 60cm tent is enough for several Kratky containers or a small DWC system.
Do I Need Special Water for Hydroponics?
Tap water works for most home setups. The two things to manage are chlorine (let water sit uncovered for 24-48 hours before use) and starting pH (adjust to 5.5-6.0 after adding nutrients). If your tap water is very hard, high mineral content can interfere with nutrient balance over time, and filtered or reverse osmosis water gives more consistent results.
What’s the Difference Between Hydroponics and Aquaponics?
Hydroponics feeds plants with a manufactured nutrient solution. Aquaponics combines fish and plants in a closed loop: fish waste provides nutrients for plants, and plants filter the water for the fish. Aquaponics is more complex to set up and balance, but can be largely self-sustaining once established. Hydroponics is the more practical starting point for apartment growers.
How Long Before I Get My First Harvest?
Fast-growing leafy greens like lettuce are typically ready in 3-4 weeks from planting. Basil takes a similar amount of time. Slower crops like kale or spinach take 5-6 weeks. Fruiting plants like tomatoes take 10-16 weeks and need significantly more light and nutrients.
Will Plants Grow in a North-Facing Apartment?
They can, but you’ll need a grow light. North-facing windows in the northern hemisphere don’t receive direct sunlight, and most food crops need the equivalent of 6-12 hours of direct light to grow productively. A clip-on LED grow light compensates for this effectively and costs $20-35.