Hydroponics Made Easy: EBB & FLOW

This advanced hydroponic technique is also called "Flood and Drain", the ebb and flow method. It gives growers absolute control over the plant root system and their nutrient supply. Read more!

• To begin with, it should be noted that Ebb & Flow – this is already hydroponics for demanding users. The hydroponic cultivation technique used on so-called EB tables, noted for its exceptional efficiency, is therefore intended rather for advanced, experienced growers.
• As we mentioned above, with EBB & FLOW you have almost 100% control over the entire cultivation process, and what is the biggest advantage for more experienced growers can cause unnecessary damage in the early stages. However, as the saying goes, no one is born learned, and everyone has to start somewhere, so theoretical preparation will only benefit you, whether you consider yourself a seasoned grower or are just beginning to experiment with hydroponics. In the early stages or even before you start, read the introductory article about hydroponics HERE.
• The table top, which consists of a shallow filling tray, is filled with nutrient solution at regular intervals and after a few minutes is drained away again.
• Plants are either in individual pots, or the entire tray is filled with growing medium.
• We recommend the complete ebb tray system from General Hydroponics, which you can also see in the image below.
• EBB FLOW offers growers maximum flexibility when it comes to continuous adjustment and control of irrigation to supply plants with required nutrients.
• This method is widely used not only for herbs, fruit or vegetables but also for ornamental plants, which when grown with EBB FLOW systems may not need repotting for several years.

• When growing with the EBB & FLOW system, residues of nutrients from the last irrigation dissolve during the re-flooding of the substrate.
• This effectively prevents the formation of undesirable deposits and their direct consequence in the form of over-fertilization of plants due to excessively high nutrient concentration.
• All irrigation that exceeds the so-called water holding capacity of the substrate immediately drains back into the reservoir with the nutrient solution.
• One of the most important things a grower must monitor when using the EBB FLOW method is choosing the correct irrigation cycle. That way the roots have enough oxygen and nutrients and you avoid overwatering.
• Irrigation is supplied to the plants using a pump.
• Individual cycles are controlled by timers.
• Most EBB FLOW systems are designed so that the nutrient reservoir is located beneath the pots or the growing plates filled with substrate and plants.
• "FLOOD": Water with nutrients is usually brought up to two-thirds or three-quarters of the height of the growing medium, and even higher for young plants whose short roots do not reach deep enough.
• "DRAIN": Once the nutrient solution reaches the required level, it stops being pumped by the pump and returns to the reservoir.

As we already mentioned, irrigation frequency is decisive — so how do you set it correctly?

• The optimal interval length between flood and drain cycles primarily depends on the size and depth of the EB table.
• The choice of substrate also matters (see below). Irrigation frequency must be adapted to the given substrate's water retention properties.
• Expanded clay (Hydroton): irrigation 2 to 3 times a day.
• Rockwool: irrigation once a day (i.e. rockwool retains more water than clay pebbles or granules).
• These are starter intervals. As soon as the plants, or rather their roots, have grown, the irrigation frequency is gradually increased... There is no universal guide because of the individual needs of plants. All the more reason to observe your plants from early developmental stages. As beginners, you face the difficult task of avoiding both overwatering and drying out. Experienced growers will tell from observation whether plants need more or less irrigation. In the first case, you will at least gain that experience.
• A helpful practical rule is to let the substrate dry out slightly before each next irrigation.
• Finding the right irrigation regime is the essence of the whole method, and once you succeed, congratulations — you have mastered a very advanced cultivation challenge!
• To help you achieve this, one practical tip: record carefully from day one how much water is used from the reservoir, noting that the water level should never reach the bottom of the pot or growing plate.
• Young plants need less water than older, more mature plants.
• It can also matter whether you are growing drought-loving or moisture-loving plant species using this hydroponic technique.
• As a general rule, water plants during the warmest part of the day.
• In winter, plants require less irrigation than in summer.
• If you need to water more frequently due to specific fertilizers diluted in a certain amount of water, shorten the intervals between irrigations but do not overwater the plants all at once unnecessarily.
• If you identify pests on your plants, among other measures reduce irrigation and water only once a day; with heavier infestation you can temporarily water only every second day.

Which substrate to use?

• Within the hydroponic flood and drain method inert media are used, such as expanded clay (Hydroton), perlite, rockwool or other inert media suitable for hydroponics.
• Expanded clay (Hydroton) requires somewhat more frequent irrigation than perlite.
• Remember that the substrate should not reach higher than 1 cm below the edge of the growing container.

Shallow or deeper system?

Deeper systems use a larger volume of nutrient solution and provide more space for the plant root system. In addition, old air is expelled from the root zone each time the substrate is flooded with fresh nutrient solution. Excess water returns to the reservoir and meanwhile beneficial fresh air reaches the roots. The time for aeration of the roots is significantly longer than in shallow EBB & FLOW systems. In deeper systems it takes longer for the substrate to dry out, requiring less frequent irrigation.

If you have any questions about hydroponic cultivation using EBB & FLOW systems, feel free to contact us at the known address info@higarden.cz.

We also recommend these products:

• Ebb&Grow General Hydroponics - complete ebb tray system (4 999 Kč)
• BioNova Starter pack Hydro Supermix (1 990 Kč)
• VitaLink Clay Pebbles, 45l Hydroton (369 Kč)

What to read next?

• How to prepare rockwool?
• What are Cal‑Mag products for and how to use them?
• Reverse osmosis (RO)