Best Plants for Aquaponics

The best plants for aquaponics are leafy greens and herbs: lettuce, Swiss chard, kale, bok choy, basil, mint, parsley, chives and watercress. They need few nutrients, grow fast and do well in every type of system, which is why they are the first crops to plant in a new setup. Fruiting crops such as tomatoes, peppers, cucumbers and strawberries also grow well, but only once the system is established and carries enough fish to feed them. Root crops such as carrots and onions need a deep media bed.

That split comes straight from the FAO manual Small-scale aquaponic food production, which notes that more than 150 vegetables, herbs, flowers and small trees have been grown in aquaponics, and groups them by how much nutrient they need. It is the same rule this guide started with in 2019: a small system with few fish suits greens and herbs, while a larger system with more fish waste can take on tomatoes, peppers and fruit. Below are 38 plants sorted that way, with FAO’s pH, temperature and harvest times for the most popular ones, what to avoid, and what you need to get seeds started.

The 38 Best Plants for Aquaponics at a Glance

Nutrient demand follows FAO’s groups where FAO names the plant; the rest are our own rating on the same scale. Difficulty assumes a home media bed system.

How Nutrient Demand Decides What You Can Grow

In aquaponics the fish feed is the fertilizer, so what you can grow depends on how much fish, and how much feed, the system carries. FAO splits crops into two groups. Low-nutrient-demand plants include the leafy greens and herbs, such as lettuce, chard, salad rocket, basil, mint, parsley, coriander, chives, pak choi and watercress, plus legumes such as peas and beans. High-nutrient-demand plants are the botanical fruits: tomatoes, eggplants, cucumbers, zucchini, strawberries and peppers. Cabbages, kale, cauliflower, broccoli and kohlrabi sit in the middle, bulbs and roots such as beets, onions and carrots need medium to high levels, and radish needs less. New Mexico State University’s guide H-170 draws the same line: lettuce, basil, spinach, chives, herbs and watercress for low to medium nutrients, and tomatoes, cucumbers and peppers only in systems with high fish stocking.

Balance the Fish With the Grow Bed

FAO’s feed rate ratio puts numbers on it: 40 to 50 g of fish feed per day for each square meter of leafy greens, and 50 to 80 g for fruiting vegetables. In US terms that is roughly 4 to 5 g of feed a day per square foot of lettuce, and 5 to 7 g for tomatoes. If your fish eat 1% of their body weight a day, 10 kg (22 lb) of fish produce about 100 g of feed, enough for about 2 square meters, or 22 square feet, of greens.

Start With Greens, Add Fruiting Crops Later

FAO recommends starting a new system with fast-growing, robust, low-demand plants such as salad greens and beans or peas, and waiting two to three months before planting larger fruiting vegetables. It also warns that plants grow a little slower than in soil or hydroponics for the first six weeks, and that new systems are often short of iron for the first two to three months, for which it suggests chelated iron. Once nutrients have built up, which FAO says takes one to three months, it reports plant growth two to three times faster than in soil.

Keep the pH Where Everyone Is Happy

Most plants tolerate pH 5.5 to 7.5, according to FAO, but fish and the nitrifying bacteria want more alkaline water, so the compromise for an aquaponics system is pH 6 to 7. Outside the plants’ range, nutrients such as iron, calcium and magnesium get locked out even when they are in the water. A weekly test with a liquid kit catches drift before the leaves show it.

Growing Guide for 12 Popular Aquaponic Crops

FAO’s appendix of vegetable guidelines covers the twelve most popular aquaponic crops. We converted its temperatures to Fahrenheit:

Source: FAO, Appendix 1. The pattern is clear: greens and herbs harvest in about a month, fruiting crops in two to four.

Leafy Greens

Leafy greens are the backbone of aquaponics: low nutrient needs, short growing times and they suit every system type, including raft and NFT. FAO notes most of them grow best in cool water, 14 to 20°C (57 to 68°F), and bolt, turning bitter, at 26°C (79°F) and above.

Lettuce

The classic first crop. FAO gives lettuce a pH of 6.0 to 7.0, a temperature range of 15 to 22°C (59 to 72°F) and a harvest 24 to 32 days after planting out, and it does well in media beds, rafts and NFT pipes alike. Loose-leaf and butterhead types are the easiest; harvest outer leaves and the plant keeps going. In a warm tilapia system, plant lettuce in the cooler months.

Kale

Kale is a brassica, which FAO places in the medium-demand group, a step above lettuce. It is still an easy crop for a system a few months old, tolerates cool water and keeps producing if you pick the lower leaves. A good choice next to trout or perch tanks.

Spinach

NMSU lists spinach among the low to medium-nutrient plants well adapted to aquaponics. It is a cool-season crop that bolts quickly in warm water, so it is easier in a cold-water system or in winter than next to a heated tilapia tank.

Swiss Chard

One of the most forgiving crops there is. FAO gives chard a wide pH range of 6 to 7.5, 16 to 24°C (61 to 75°F), a harvest in 25 to 35 days, and recommends it for every system type. The colored stems make it as good-looking as it is productive, and it handles warmer water better than lettuce.

Arugula (Salad Rocket)

FAO lists salad rocket with the low-demand greens. It grows fast from seed, tastes peppery and, like most greens, prefers cooler water. Sow a few plants every couple of weeks for a steady supply.

Bok Choy (Pak Choi)

Pak choi is on FAO’s low-demand list and is one of the quickest Asian greens. Harvest it young as baby bok choy or let it size up; either way, it suits raft systems especially well.

Radish Sprouts and Microgreens

FAO notes radish needs fewer nutrients than other root crops. Grown as sprouts or microgreens, it is ready in days rather than weeks and works even in a small system. Full-size radishes need a media bed deep enough for the root.

Herbs

Herbs are the best value crop in aquaponics: low nutrient demand, small space and a high price at the store. Most of the herbs below are on FAO’s low-demand list or close relatives of plants that are.

Basil

FAO calls basil one of the most popular herbs in aquaponics, including in commercial units, and an ideal plant because of its high nitrogen uptake. It wants warmth: 18 to 30°C (64 to 86°F), best 20 to 25°C (68 to 77°F), and pH 5.5 to 6.5. Start harvesting after five to six weeks, when plants reach about 6 inches, by pinching tops. The perfect partner for a tilapia tank.

Mint

Mint is on FAO’s low-demand list and grows almost too well: in a media bed its runners will take over. Give it its own corner or a separate net pot, and cut it back often.

Chives

Another low-demand herb on FAO’s list. Chives regrow after every cut, tolerate a wide range of conditions and add purple flowers that are edible too.

Watercress

Watercress grows naturally in running water, so an aquaponics system suits it perfectly. FAO lists it among the low-demand herbs. It roots easily from cuttings and is a good plant for the edge of a raft bed.

Wheatgrass

Wheatgrass is a sprouted grain cut young for juicing. It needs little from the water and grows in a shallow tray or a corner of a media bed. Harvest it within a couple of weeks of sowing and resow.

Cilantro (Coriander)

Coriander is on FAO’s low-demand list. It bolts quickly in heat, so sow small batches often and grow it in cooler water or in winter. Let a few plants flower if you want coriander seed.

Parsley

FAO’s growing guide covers parsley in detail: pH 6 to 7, 15 to 25°C (59 to 77°F), first harvest 20 to 30 days after transplanting, and suitable for media beds, NFT and raft systems. It is a biennial, so a single planting keeps producing for many months.

Oregano

A hardy Mediterranean herb that does well near the top of a media bed, where the roots are moist but not waterlogged. Frank Wood, who wrote the first version of this guide, said of oregano that he “really couldn’t cook without it”.

Rosemary

Rosemary is a woody herb that likes well-drained roots, so give it the highest, driest spot of a flood and drain bed rather than a raft. It is slow to start from seed; a rooted cutting gets you there faster.

Lavender

Like rosemary, lavender prefers its roots on the dry side, so plant it high in a media bed. It is grown more for scent and flowers than food, though the flowers are edible, and it attracts pollinators if the system is outdoors.

Thyme

A low, spreading herb that is easy to keep in a media bed. Treat it like oregano: a well-drained spot and regular trimming.

Anise

The annual herb anise (Pimpinella anisum) grows like its relatives dill and coriander and is easy enough in a media bed. Star anise is a different plant altogether, a tree, and not a realistic aquaponics crop.

Chili Peppers

Peppers are on FAO’s high-demand list, so plant chilies in an established system. FAO’s pepper guidance applies: pH 5.5 to 6.5, warm days of 22 to 30°C (72 to 86°F), media beds, and 60 to 95 days to harvest. A chili plant can keep cropping for a long time in a warm greenhouse. Frank Wood called chili peppers “one of my all time favorite plants”.

Edible Flowers

FAO notes that edible and ornamental flowers are grown in aquaponics too. Nasturtiums, calendula and violas are popular choices. Flowering takes more nutrients than leaves, so give them a system that is a few months old.

Fruiting Vegetables and Other Vegetables

These are the crops most people build an aquaponics system for, and the ones that need the most planning: more fish, a mature system, and in most cases a media bed at least 30 cm (12 inches) deep, which FAO says lets you grow every category of vegetable.

Tomatoes

Yes, tomatoes grow well in aquaponics, and they are the most popular fruiting crop. FAO gives pH 5.5 to 6.5, days of 22 to 26°C (72 to 79°F) with nights of 13 to 16°C (55 to 61°F), and a first harvest 50 to 70 days after planting; indeterminate varieties can keep fruiting for eight to ten months. Because tomatoes are very hungry, especially for potassium, FAO says to plan the number of plants around the fish biomass. Stake or trellis them, and remove side shoots on indeterminate types.

Sweet Peppers

Bell peppers share chilies’ needs: high nutrients, warm days and a media bed. FAO’s guide puts them at 60 to 95 days. They pair well with a warm-water fish tank.

Cucumbers

FAO says cucumbers like long, hot, humid days, 22 to 28°C (72 to 82°F), and are ready in 55 to 65 days in media beds or rafts. They are vigorous vines, so trellis them upward to save bed space, and keep an eye on powdery mildew in humid greenhouses.

Beans

Beans are an easy early crop because, as legumes, FAO puts them in the low-demand group. Climbing varieties use vertical space; FAO’s guide gives 50 to 110 days to maturity depending on the variety.

Squash and Zucchini

Zucchini is on FAO’s high-demand list, and squash plants get big. Grow one or two in a large media bed, train the vines away from the walkways, and expect them to shade their neighbors.

Peas

Like beans, peas are low-demand legumes in FAO’s grouping. They are a cool-season crop, so they suit winter systems and cold-water fish. Give them netting to climb.

Broccoli

FAO gives broccoli pH 6 to 7, an average temperature of 13 to 18°C (55 to 64°F) and 60 to 100 days from transplanting, in media beds. Harvest while the buds are tight; once yellow flowers open, the head is past its best.

Cauliflower

FAO lists cauliflower as medium demand, with pH 6.0 to 6.5 and two to four months to harvest. It is the fussiest brassica here: it wants warmth while growing and cooler conditions, 10 to 15°C (50 to 59°F), to set its head, so time it for spring or autumn.

Cabbage

FAO calls cabbage a winter crop, best at 15 to 20°C (59 to 68°F), with growth stopping above 25°C (77°F), ready 45 to 70 days after transplanting. It needs a mature system and room: FAO spaces head cabbage 60 to 80 cm (2 to 2.5 feet) apart.

Onions

FAO puts bulbing plants such as onions in the medium to high-demand group and recommends growing root and bulb crops in deep media beds or wicking beds attached to them. Green onions and scallions are the easy way in. Frank Wood counted onions among the best plants for aquaponics he had grown.

Carrots

Carrots are possible but not easy. FAO says root crops need special attention and only succeed in deep media beds or wicking beds, because the root has to grow straight down through the media. Choose short varieties, keep the bed deep and loose, and expect odd shapes.

Fruits and Small Trees

These are long-term plants for a large, mature system with plenty of fish. They are rewarding, but none of them is a beginner crop.

Strawberries

Strawberries are on FAO’s high-demand list. They are popular in vertical towers and NFT channels because the fruit hangs clean and dry. Give them a system a few months old, and remember indoor plants need hand pollination.

Dwarf Citrus Trees

Dwarf lemons, limes and oranges need a deep media bed, steady nutrients and years of patience, but they are evergreen and productive. Frank Wood described dwarf citrus as “one of my personal favorites to grow with aquaponics”. Watch for yellowing between the leaf veins, a common sign of iron shortage.

Dwarf Pomegranate

Similar demands to citrus: a deep bed, a mature system and a warm, sunny spot. Dwarf varieties stay small enough for a greenhouse bed and are ornamental even before they fruit.

Bananas

Bananas are a showpiece for big tropical or greenhouse systems: huge leaves, heavy nutrient demand and a strong root system. In most of the US they need a heated greenhouse to fruit.

Melons and Watermelons

Melons are hungry, sprawling and heavy. Grow them only in a large media bed, on a strong trellis with slings for the fruit, and in a system with plenty of fish.

Pineapple

A fun experiment rather than a crop: pineapples need warmth and take a long time, often more than a year, to fruit. Start one from a store-bought top in the corner of a warm media bed.

Plants to Avoid in Aquaponics

Almost anything will grow, but some plants are more trouble than they are worth:

• Root crops in raft or NFT systems. FAO says root crops such as carrots, beets and turnips can only succeed in deep media beds or wicking beds; potatoes are harder still. In water-only systems the roots rot or never form.
• Acid-loving plants such as blueberries and azaleas. They want much more acidic conditions than the pH 6 to 7 an aquaponics system has to hold for the fish and bacteria.
• Very large or sprawling crops such as corn, pumpkins and full-size trees in a small system. They take bed space and nutrients that could feed many smaller plants.
• Anything treated with pesticides. Bought seedlings may have been sprayed, and FAO says chemical pesticides must never be used in aquaponics because they could harm the fish. Start from seed or wash and quarantine new plants.
• Seedlings in soil. FAO does not recommend transplanting soil-grown seedlings because soil can carry plant pathogens; if you must, wash every bit of soil from the roots.

Plants That Should Not Go in the Fish Tank

Keep crop plants in the grow beds, not in the fish tank. Decaying leaves foul the water, and parts of some plants are toxic: tomato, pepper and potato leaves belong to the nightshade family. If you want plants in the tank itself, use aquarium plants, or let the fish graze duckweed, which FAO mentions as a supplementary feed for tilapia.

Best Plants for Each Type of Aquaponics System

Media Beds

The most flexible system. FAO says a media bed at least 30 cm (12 inches) deep can grow every category of vegetable, and that home growers commonly mix greens, herbs and fruiting crops in the same bed, which lets shade-tolerant greens grow under taller plants. Expanded clay is the usual media; our clay pebbles guide covers the choice and our grow bed guide covers depth and sizing.

Raft (Deep Water Culture)

Best for lettuce, basil, chard, bok choy and other greens, which sit in net pots in a floating raft with their roots in the water. FAO notes rafts are mostly used for monoculture because you are limited to the holes in the raft. Tomatoes and cucumbers can grow in rafts, per FAO’s guide, but need support.

NFT Channels and Towers

Good for greens, herbs and strawberries. FAO warns that fruiting plants in NFT need large, flat-bottomed pipes and wide spacing, and that they wilt almost at once if the water flow stops.

Fish Tank and Desktop Systems

A small tank with a grow tray on top suits herbs, lettuce, microgreens and houseplants. With only a few small fish, nutrients are limited, so skip fruiting crops. See our guides to the aquaponics fish tank and ready-made aquaponics kits.

Match Your Plants to Your Fish

Plants and fish share the same water, so their temperature ranges have to overlap. FAO says it is the water temperature, more than the air, that has the greatest effect on the plants.

• Warm-water fish such as tilapia, which grow best at 81 to 86°F, pair with basil, peppers, chilies, tomatoes, cucumbers, okra and squash. Lettuce bolts in that water.
• Cool-water fish such as rainbow trout, at 57 to 61°F, pair with lettuce, spinach, kale, chard, cabbage, broccoli, peas and cilantro.
• Middle-range fish such as catfish, perch, koi and goldfish suit a mix, shifting with the seasons.

Our guide to the best fish for aquaponics lists each species’ temperature range.

How to Start Plants in an Aquaponics System

Start Seeds in Inert Media

FAO recommends starting seeds in propagation trays filled with inert media such as rockwool, coco fiber, vermiculite or perlite, so the seedlings can move into the system without soil and with minimal shock. Keep growing them for at least two weeks after the first leaves appear; FAO suggests transplanting basil, for example, once it has four or five true leaves.

Use Net Pots in Rafts and NFT

In raft and NFT systems each seedling sits in a slotted net pot, held in place with a few clay pebbles around its starter cube, with the roots reaching down into the water.

Plant Directly Into Media Beds

In a media bed, push the media aside, set the seedling in, and backfill. FAO advises planting at the highest point the water floods to, about 5 to 7 cm (2 to 3 inches) below the surface, not deeper, to avoid collar rot, and planting at dusk so the seedling has a night to settle in. You can also sow seeds directly into the bed; FAO suggests removing the bell siphon while you do, so the seeds do not wash around.

Pollinate Fruiting Crops Indoors

Tomatoes, peppers, cucumbers, squash, melons and strawberries all need pollination to set fruit. Outdoors, insects do it. Indoors or in a closed greenhouse, do it yourself: gently shake tomato and pepper flowers, or move pollen from male to female flowers of cucumbers and squash with a small brush. Leafy greens and herbs need no pollination at all, since you harvest the leaves.

Stagger Your Planting

FAO recommends planting and harvesting in a staggered cycle rather than all at once, because a bed of plants all maturing together will swing the nutrient levels. Sow a few greens every one or two weeks and you get a steady harvest and steady water chemistry.

Before you plant: cycle the system, choose your fish, and see how to build an aquaponics system.

Best Plants for Aquaponics FAQ