While I love to grow herbs in my garden, there’s something special about growing herbs indoors. It’s pure magic to watch them grow from a tiny seed right on my kitchen counter. It’s hard to beat the convenience and fresh flavor of herbs picked just moments before they’re cooked. Herbs are also some of the easiest plants you can grow indoors. They’re an excellent choice for beginners who want to try indoor gardening.
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What is hydroponic growing?
Hydroponic growing is a way to grow plants without soil or dirt. If you’ve ever let a cutting set root in a glass, then you’ve already used the easiest of all home hydroponic rigs. A glass of water, a little light, and hope!
All hydroponic setups require a few basics. One is a place for the plant to grow. This is referred to as the medium or substrate. You also need a way to provide your plants with the nutrients they need. Most home hydroponic rigs do this through a nutrient solution, a mixture of essential elements and minerals dissolved in water. Finally you need something to hold the plants and control how they are fed, like a tank or some irrigation pipes. For most home systems a source of light is also important.
It might sound complex, but it doesn’t have to be any harder than growing herb pots on a window sill. There’s a lot of excellent easy-to-use home hydroponic kits available these days, like the AeroGarden, allowing anyone with a power-point and a bit of spare time to have the fantastic taste of crisp herbs whenever they fancy.
Do all herbs grow well in hydroponics?
Most herbs thrive when grown with an indoor hydroponic herb garden. Leafy ones like basil and parsley are the best type of herbs to grow for beginners. They’re tough plants with consistent, easy to manage needs. They don’t require special care for their roots like carrots or potatoes, and they don’t need to be coddled into producing flowers or fruit. All you need to do is keep them alive and they’ll just keep popping out aromatic leaves, ready for the table.
For a home grower, however, it’s best to stick to the fast growing leafy herbs. Larger, woodier plants like rosemary or sage will sometimes take over the whole rig, producing too much by way of stems and stalks and not enough delicious foliage.
The best Hydroponic herbs to grow indoors:
Basil is the absolute easiest plant to grow hydroponically and one of my favorite herbs all round. They grow well from seeds and cuttings alike, have a free and easy attitude to things like heat, light and the contents of their nutrient solution. They also shoot up faster than you’d think possible, producing edible leaves in just a few weeks. I go into more detail on how to grow hydroponic basil here, but the hot take is that if you want to grow fresh herbs you can’t go past it.
Parsley is another choice well suited to beginners finding their way with hydroponically grown herbs. Their seeds sprout readily in most growing media and they really aren’t fussy about their light levels or temperature. Curly leaf varieties are most common. Personally I like flat leaf Italian style parsley the best. it thrives with very little effort, and has a rich peppery flavor that that brings out the best in other herbs in the meal, too.
While dried herbs have their uses, there’s nothing like the flavor of a freshly chopped harvest of dill. They’re also beautiful! Their delicate foliage grows in neat compact clusters that’s well suited to an indoor herb garden. It also responds favorable to regular cutting. Each harvest just prompts it to grow thicker and better! You do need to watch the temperature around it, as they like a cooler growing environment.
Oregano is another firm favorite that’s a classic addition to pizzas and pasta. They’ll happily sprawl up and out, as they grow as a ground cover in beds outdoors. They like warm weather and lots of light, so they grow well with other fast growing staples like basil and parsley. I personally love to dry the excess for later use to bring a different dimension to the herb’s characteristic flavor.
Also known as coriander, there’s no doubt that fresh cilantro brings a special flavor not found in dried leaves at all. It’s one of the best herbs to grow as a beginner. It’s a vigorous and hardy plant responds to warm temperatures and good lighting with dense thickets of aromatic leaves, perfect for fresh pico de gallo, pho or cooling chutneys.
Mint is fast grower that is so robust it often takes over garden beds when grown in conventional garden soil outside. You can tame its wild ways by growing in hydroponics instead. Its hardy nature make it a great choice for novice growers. So long as you keep the roots well fed and watered, you’ll be up to your eyebrows in leaves in no time. It also smells great, releasing that wonderful fresh scent every time it’s touched.
Watercress is one of the best options for smaller systems. It’s a compact grower that can be eaten at any point . The young plants are crisp and sweet, and more mature leaves develop a characteristic gentle pepperiness that plays well with other vegetables. They germinate so easily that I’ve often just grown them as a microgreen on a bit of damp paper towel. They really want very little and give a lot in return.
Thyme is an excellent companion plant for most of the herbs I’ve mentioned so far. It tends to be compact and is easy to keep beside hungrier, larger crops. Thyme does tend to be a slower grower, but has lower nutrient requirements than most hydro herbs. It’s also more forgiving of the odd mistake we all make here and there.
What’s needed to grow hydroponic herbs
The first thing you’ll need to get growing at home is a hydroponic system. While it can be a bit bewildering, there’s no reason you can’t start with a hydroponic herb garden kit. They generally come with plug-and-play style seed pods, ready to use plant food and inbuilt lighting and filter systems.
I’m a big fan of the AeroGarden range for just how easy they make growing your own herbs hydroponically, especially for those of us with limited space or time to devote to the cause. They’re a good choice for those who want make a start growing herbs hydroponically at home as they’re some of the easiest types of hydroponic systems on the market.
That said, it’s really rewarding to develop your own hydro herb garden setup. The easiest place to start is with Deep Water Culture setups. At its most basic this technique involves growing the herbs in a soil-free medium with their exposed roots submerged in water. Kratky setups are literally just a bucket filled with water and nutrients, with a hole in the lid for the plant itself to sit. They’re fantastic for herbs that grow quite large if well fed, like basil.
More enduring hydroponic systems will also involve a pump to keep the nutrients circulating past the roots of the herbs. They also involve a way to add oxygen to the liquid.
Building your own system has its own benefits and drawbacks. There’s more to decide, and you have more control over things like the chemical composition of the solution, the light level and how large the whole shebang can become. Once you have the hang of it, you might want to try a Nutrient Film Technique setup, or an ebb and flow rig that allows for much bigger herbs grown in a large bucket or bag of medium instead of in water.
Lighting is critical to the success of your hydroponic garden. No light means no growth, even for hardy plants like oregano or mint.
If you want to stick with natural light, you’ll need a brightly lit porch or room with lots of sun. A southern aspect is best as it will catch the most light through the day, and a south-eastern facing room or balcony will catch the morning sun and give a boost to your growth.
For most of us though a grow light is a must-have. Artificial lighting means you can give herbs in a hydroponic rig summer conditions all year round and ensure a near infinite supply of delectable leaves. High efficiency LEDs are a good choice, as they provide plenty of light using very little electricity. They’ll make sure every plant thrives no matter what the weather.
Water and Nutrients
Plants grown in hydro must take everything they need to thrive from the water in the system. It’s their food and drink, nurturing them from the roots up. You’ll need to make sure your little garden is appropriately fertilized and watered if you want to see the best results.
There’s two big things you need to monitor in your nutrient solution. First is how rich the solution is in fertility. One way to track this is to just work out how much material is dissolved in the liquid when mixed. This is the Parts Per Million measurement, or PPM. The other is a bit more subtle and involves testing how well the liquid conducts electricity. This is known as the Electrical Conductivity and is a more common way of discussing what level of nutrition herbs prefer.
The other important characteristic of your water is its acidity. Measured in pH, this controls what the roots of the herbs get to utilize. Many herbs prefer mildly acidic or neutral conditions, which has the added benefit of protecting the root system from fungi that otherwise love to grow in the water. While pH is easy to monitor, it’s a bit trickier to control and requires a deft hand once your system gets beyond a certain size.
If you’re just starting out it’s fine to use premixed solutions. Many commercial kits will contain a hydroponic nutrient blend suited to the system and the seeds already included in the kit. You can can also buy nutrient blends. Aim for one that’s intended for leafy green vegetables to ensure it’s high in nitrogen. They’ll generally be at pH that suits the more popular herbs, too.
“The process of nutrient management and absorption is critical to management of a hydroponic system, since plant can only absorb nutrients that have been dissolved in the water by the grower, or are present in the raw water supply.”Mark Huey, Horticulture Technologist, Department of Agriculture, Environment and Rural Affairs, UK.
How fast do herbs grow in hydroponics?
Much depends on what sort of herb you’re growing, the level of light and the state of your water supply. Different types of herbs just grow faster than others even in hydroponics. Basil, mint and oregano put out new leaves at rates that beggar belief sometimes, while others like thyme don’t rush things. Keep things warm and well lit and you’ll get plenty to eat in no time.
How long do hydroponic herbs last?
Most herbs are perennials They’re plants that grow continuously without dying off each year. Give them consistent light, warmth and nutrition, and there’s no reason they won’t keep popping out new leaves indefinitely. Even many that are typically grown as annuals will just keep rocking on all year if they never get to feel a true winter.
The big limiting factor for any plant grown in hydroponic systems is space. Many will grow to sprawling shrubs given half a chance even with regular pruning. You also have to watch out for root that fill out tubs and pipes over time. Without space the plant will falter. As a result, small countertop systems often see plants die back after six months to a year.
Do hydroponic herbs taste different?
A lot of research has looked at whether herbs cultivated in hydroponic setups have better flavor and aroma than herbs grown in soil. People claim to be able to taste the difference, but it’s often not true. Most supermarket herb production is hydroponic and their crops taste no worse for it. Their flavor comes from the same place as any other culinary herb. With good lighting and the right nutrients, they all taste much the same.
Can you plant hydroponic herbs in soil?
So long as the roots are strong and the plant is healthy it’s totally possible to move herbs from hydro to a garden bed. In fact it’s often how the herb seedlings found in garden stores are produced. They’re generally sprouted in soil free seed starting plugs before being transplanted to pots. You’ll need to take your time and move them outside gradually. They’re used to the home environment so make sure you harden them off before planting into garden beds.
When it comes to growing herbs at home, I can’t recommend raising oregano, basil and cilantro inside right on your kitchen counter. All kinds of different herbs can be grown right where you want to eat them for the freshest flavor. And really, learning how to grow our own food makes the meal taste all the better!