DIFFICULTY | GROW CYCLE DAYS | GERMINATION DAYS | GERMINATION CONDITIONS | SEED PREP. |
easy | 7+ days (using grow lights) | 3 days | stacked with weight | none |
SUPPLIES
3 Bootstrap Farmer microgreen trays
2x trays without holes + 1x tray with holes
Grow medium
we recommend loose coco coir
Water & sprayer
in the absence of a water source with spray nozzle, we recommend a pressure sprayer
SowYummy Broccoli seeds
1 portion per 1010 tray, or 2 portions per 1020 tray
Clean shaker - optional but recommended for sowing Broccoli seeds
we recommend a clean seasoning bottle/container or parmesan cheese shaker
10-15 lb weight
PRO TIP Avoid plastic shakers as they create static which can make it cumbersome to shake out the seeds
PREPARE TRAY
If using a medium other than loose coco coir, prepare it according to manufacturer's instructions.
Nest the tray with holes inside one tray without holes.
Pack the tray with coco coir about 3/4 full. We use approximately 2 1/4 litres of loose coco coir per 1020 tray, or 1 1/4 per 1010 tray. If the tray is too full this will allow too much light in and impede germination, but if it's not full enough harvesting will be more difficult.
Be sure to distribute the coco coir as evenly as possible throughout the tray and into the sides and corners to ensure good water retention.
Gently press the second tray without holes over the top of the coco coir to even out the surface. You don't need to press too hard, we are not compressing it just smoothing it out. Don't worry about the minor channels created by the tray, these will smooth out during watering and don't affect germination or growth.
CONDITION GROW MEDIUM
In a pinch you can use a spray bottle for this step, however, to ensure adequate saturation a spray bottle will be onerous.
Using your pressure sprayer set to medium/light intensity, spray over the grow medium in a zigzag pattern from edge to edge, starting at the top of the tray, slightly overlapping each stroke. We find that 2-3 passes over the tray are sufficient.
The medium needs to have enough water to sustain germination for about 3 days, but not be so wet that fungus will grow or that young shoots start to rot while in germination. Think damp not soggy.
To check if your medium is adequately saturated, make a small hole in a corner of the tray with your finger. The coco coir should be wet all the way through but not dripping into the bottom tray
PRO TIP If you're working indoors and are concerned about water on floors or other surfaces, place your tray inside an adequately sized storage bin to contain the overspray.
SOW SEEDS
Using a shaker, broadcast seeds as evenly as possible all over the grow medium.
Avoid clumping as that impedes air circulation and air circulation is vital to the health of your crops. Fungus and damping off disease are common in environments with poor air circulation.
Give the seeds a light misting of water to activate them.
In the video below we are using mustard seeds because they are light yellow, making them easier to see against the coco coir.
GERMINATION
Stack the second tray without holes in a nesting position over the sown seeds. Place your weight on top. We use sandbags weighing approximately 15lbs.
Place the tray in a cozy area where it can stay undisturbed for a few days. A temperature of at least 20 degrees Celsius (68 Fahrenheit) is needed for healthy and even germination.
PRO TIP If heating your space is not an option, you can use a seedling heat mat under your tray.
You can check your germination progress on the second day to make sure you don't have any dry spots on the tray. Remove the weight and gently lift the top tray. If you notice dry spots mist with water. Replace the top tray and weight.
PRO TIP When calculating germination/grow cycle days, we consider the day you planted your seeds as day 0.
BLACKOUT
By the third day you should see small microgreens start to poke out around the edge of the top tray.
At this stage put the microgreens into blackout by removing the weight, and flipping over the top tray to create a dome, placing it over the greens like a lid. This is to force the microgreens to stretch looking for light, forcing them to grow a bit taller which will make harvesting a little easier.
Leave in blackout for 1 day.
LET THERE BE LIGHT
On day 4, remove the weights and top tray, and check your crop for any signs of problems. If all is well, place your microgreens under lights. Most of the microgreens at this stage will be yellow but they should have mostly straightened out during blackout. As they photosynthesize they will turn green.
On the first day under light give your microgreens a generous bottom watering, almost a cup.
To bottom water, lift only the tray with holes and pour water into the bottom tray without holes, then lower the tray with holes. The grow medium and microgreens will absorb the water through capillary action.
HAPPY & HEALTHY GROWTH
You can grow your microgreens using other light sources but we recommend using complete spectrum LED grow lights.
Give your plants 16-18 hours of light every day.
PRO TIP Even plants need to sleep so if the space where you are growing your microgreens is exposed to sunlight, schedule the time your lights are off to coincide with nighttime.
Make sure you have adequate air circulation in the space where you are growing your microgreens.
Water your microgreens daily - a little goes a long way. It's better to lightly water your microgreens twice a day then to overwater them once a day.
Remember, air circulation is vital to the health of your crops. Fungus and damping off disease are common in environments with poor air circulation and overwatering.
The edges of the tray will likely dry out fairly quickly because they are more exposed to air. We like to mist close to the grow medium (not on the plants) around the perimeter where we find dry areas.
You may notice some seed husks remain on the plants as they grow. SowYummy seeds have been tested for pathogens (including those which cause food borne illnesses) so they are perfectly safe to eat.
HARVESTING & STORAGE
We like to harvest Broccoli microgreens at the cotyledon stage, before the true leaves develop. In our experience they are most tender and flavourful during this time.
If you intended to store the harvested microgreens, make sure the canopy and stems are dry. Microgreens stored when wet will start to decompose quickly.
The best way to harvest any microgreens is using a clean and sharp knife.
Scissors can work fine if you are harvesting to serve, however, if you intend to store harvested greens, scissors are not recommended. This is because scissors tear the stem rather than cut it, and torn stems bruise and start to decompose much quicker than stems cut cleanly with a disinfected knife.
We disinfect our knives using a solution composed of 1 part 3% food grade hydrogen peroxide mixed with 2 parts filtered water.
To harvest Broccoli microgreens, using one hand gently grab hold of a modest handful of the canopy (leafy tops) and slice the knife blade across the stems a little above the substrate to avoid picking up grow medium.
Store any microgreens in a clean airtight container in the fridge. If you are going to wash them, do so only when you intend to use them.
In our experience healthy, properly harvested and stored microgreens will keep in the fridge for at least 10 days.
Happy eating!