Read on to learn more about growing microgreens on a hydroponic / jute mat.
Materials Needed
- Growing trays without drain holes
- Hydroponic Mat to fit the tray
- Seeds
- Spray bottle
- Water **
- Scissors to harvest
Note that trays may be re-used many times, and it is fine to section multiple crops per tray.
Step by Step Instructions
What follows are general instructions for growing your microgreens on hydroponic mats. While you will find that microgreens are generally easy to grow, you may need to experiment a bit to get it just right.
- ** Balance The pH Of Your Water – Microgreens seeds are sensitive to the pH of water. Use pH test strips and instructions to adjust the pH of your water. Most microgreens will do best at a pH of 6. A range of 5.5 to 6.5 is acceptable. Make sure to only water your crops with water you have balanced to an acceptable pH level. It is also helpful to use filtered water to remove any chlorine from the water.
- Step 1: Prepare Your Trays – Pour pH-balanced water into the bottom of your tray. Lay one of the growing pads in the tray and swish the water around gently. Press gently on the growing pad to make sure that the underside of it is saturated. Gently swish the tray again to ensure that the grow pad is thoroughly saturated. Finally, take the spray bottle and mist the top of the pad evenly with about 10 sprays, to make sure that there are no dry spots. Lay your tray flat in preparation for seeding.
- Step 2: Spread Your Seeds - Most seeds do not need to be pre-soaked and can be spread dry directly onto the saturated grow pad. Sprinkle seeds evenly (side to side and end to end) over the saturated grow pad. For smaller seeds (arugula, broccoli, mizuna, etc. sprinkle about 2 tablespoons. You can experiment with up to 3 tablespoons of the smaller seeds for a denser crop. For larger seeds like radish, you may want to use as much as a quarter cup.
- Step 3: Mist & Cover – Once you have a good distribution of seeds on the saturated pad, use the spray mister to spray the seeds. Spray with the mister to make sure that every seed is nice and wet. Now take one of the other trays and use your spray mister to spray the inside of it 4 or 5 times with an even distribution of mist. Use that misted tray as a black-out and humidity dome on your recently seeded tray. Your newly sown seeds need humidity and dark to thrive. Set your tray (being careful not to slosh it and disturb the dispersion of your seeds) in a place where it won’t get too hot, or too cold. 65 to 75 degrees Fahrenheit is ideal.
- Step 4: Mist Every 12 Hours – Uncover the seed tray every 12 hours or so and mist them again with your spray bottle. 10 evenly distributed sprays should do. Do not add additional water other than the misting. Recover your tray.
- Step 5: Uncover the Tray – Your crop should be ready to uncover after 4 or 5 days. You can judge this by watching for when the baby leaves (cotyledons) of your crop first emerge and then waiting one more day. It is important to keep your crop in the dark for the first 4 to 5 days to force your crop to grow in the struggle for light. This will help you grow a strong crop. Once you uncover the tray, make sure your crop gets plenty of light. We recommend LED grow lights. Direct sunlight, fluorescent, or incandescent lights are also good. If your crop angles for light, be sure to rotate the tray occasionally.
- Step 6: Check Daily – Your crop should have the right balance of water from now till harvest. Pull up a corner of the grow pad. It should be fairly damp. If necessary, replenish water to the bottom of the tray so that water comes up to halfway up the channels. Be sure to water from the bottom once the greens are uncovered, and do not use the spray bottle anymore.
- Step 7: Time to Harvest – Most microgreens will be ready to harvest in 10 days. Some crops can be harvested as early as 7 days. Most crops will not last past 14 to 17 days before they must be harvested. Keep in mind that there are exceptions to these harvest times. Details for the most popular hydroponic seeds can be found on the reverse of this instruction sheet.
- Step 8: Harvest – Move your trays to a cool, shady place. If your greens are harvested when it is too hot, they will wilt very quickly after harvesting. If harvested when cool (late evening, early morning), they will tend to stay fresh and crisp.
Recommended Harvesting Method: Grab a fistful of microgreens, and gently uproot the entire clump from the grow pad. Use scissors to trim the roots from the greens.
Alternate Method: Lift the grow pad from the tray and use scissors to trim the microgreens directly from the grow pad. Think of it as giving your greens a haircut.
- Step 9: Rinse & Dry – Use a colander to rinse your microgreens thoroughly under cold water. Dry the greens completely by spreading over a towel or paper towels and air dry. Speed drying by using a fan on a slow setting. Cut greens are best if served right after drying but can be stored loosely in a bowl in the refrigerator for several days. Do not try to refrigerate greens that are not completely dry.