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How to Care for Baby Microgreens until Harvest

Once your microgreen seeds germinate and come up above the soil line, it’ll be time to care for baby microgreens as little plants. 

Your baby greens will need some quality TLC to get them to harvest in just a week or two. The time it’ll take for maturity depends on the plant species and what you’re growing. Either way, the great thing about care for baby microgreens is that it really doesn’t take long to start enjoying the health benefits of microgreens. 

But you have to keep them alive till then. Whether you’re growing mustard greens or pea shoots, the 1-2 weeks of growth can feel like a lifetime. You’ll need to watch out for signs of plant stress or discoloration. The nutritional value will be higher in your leafy greens with good quality plant care. 

So, as you read on, you’ll find out:

  • The best care for baby microgreens until harvest.
  • How much light, water and temperature plants need to grow and thrive.
  • The secrets special touches that not everyone knows about (But you will soon!). 

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1. Light:

Two things to keep in mind when it comes to light are: 

  • Positioning: Place the trays of different types of young seedlings in a location, such as sunny windowsill with access to direct sunlight or use artificial grow lights. Microgreens require at least 12-16 hours of light per day.
  • Light Distance: If using grow lights, adjust them to maintain an appropriate distance from the microgreens. The light source should be close enough to prevent leggy growth but not too close to cause heat stress. 

While natural sunlight is always ideal, it’s not always available. Artificial light is the next best option. The optimal distance between grow lights and trays of microgreens depends on the type of lights you are using, their intensity, and the specific growth stage of the microgreens. Here are some general guidelines of lights for care of baby microgreens:

  1. Fluorescent Lights:
    • For fluorescent lights (T5 or T8 tubes), position them about 2 to 4 inches above the top of the trays. Adjust the height as needed to maintain this distance as the microgreens grow.
  2. LED Grow Lights:
    • LED grow lights generate less heat compared to some other types of lights, allowing them to be placed closer to the trays. Generally, start with the lights positioned around 6 to 12 inches above the trays. Adjust the height based on how the microgreens respond and the manufacturer’s recommendations.
  3. High-Intensity Discharge (HID) Lights:
    • HID lights, like metal halide (MH) or high-pressure sodium (HPS), emit more heat. Keep them at a greater distance, usually around 12 to 24 inches above the trays. Monitor the temperature to prevent heat stress on the microgreens.

Tips for Lighting:

  • Adjust as They Grow:
    • As the microgreens grow, adjust the height of the lights to maintain the recommended distance. This helps prevent leggy growth and ensures the plants receive adequate light.
  • Monitor Temperature:
    • Regularly check the temperature around the trays. If the lights generate too much heat, it can affect the microgreens. Provide adequate ventilation or adjust the distance accordingly.
  • Intensity Matters:
    • Different grow lights have varying light intensities. Always refer to the manufacturer’s guidelines for the specific lights you are using. If in doubt, start with a greater distance and gradually reduce it based on the microgreens’ response.
  • Rotate Trays:
    • To ensure even light exposure, rotate trays regularly. This helps prevent uneven growth on one side of the tray.
  • Use a Light Meter:
    • If precision is crucial, consider using a light meter to measure the intensity of light reaching the microgreens. This can help you fine-tune the distance for optimal growth.

It’s important to note that these lighting recommendations are general guidelines. Specific adjustments may be needed based on factors such as the microgreen variety, temperature, and the duration of light exposure. Always monitor the growth and health of your microgreen crops and be ready to make adjustments to ensure they receive the right amount of light at each stage of their development.

2. Watering:

Microgreens need lots of water and watering is very important to their short period of growth. Here’s a couple of rules of thumb when it comes to watering microgreens:

  • Consistent Moisture: Keep the growing medium consistently moist but not waterlogged. Be careful of excess water. Water gently using a spray bottle or fine mist nozzle to avoid disturbing the delicate seedlings. Microgreens prefer a consistently moist environment, but it’s crucial to avoid waterlogging, which can lead to root rot.
  • Bottom Watering: Consider bottom watering by placing the trays in a shallow container filled with water. Allow the growing medium to absorb water from the bottom. This method is a good choice because it helps prevent water from splashing onto the foliage, reducing the risk of fungal diseases.

Tips For Watering:

  • Avoid Underwatering and Overwatering:
    • Finding the right balance is key. Underwatering can lead to stunted growth, while overwatering can cause root rot and other issues. Regularly check and adjust your watering practices based on the moisture needs of your microgreens.
  • Again – Consistency is Key:
    • Consistency in watering is crucial for microgreens’ growth. Fluctuations in moisture levels can stress the plants and affect their development.
  • Monitor Seedling Response:
    • Observe how your microgreens respond to watering. Adjust your routine based on their appearance and the moisture levels in the growing medium.
  • Use a Gentle Watering System
    • Water gently using a fine mist or spray bottle. Microgreens have delicate structures, and a gentle application prevents soil disturbance and damage to the seedlings.
  • Check Moisture Levels Regularly:
    • Perform regular moisture checks by inserting your finger into the soil or growing medium. If the top inch feels dry, it’s time to water. Microgreens have shallow root systems, so maintaining proper moisture at the surface is essential.
  • Avoid Overhead Watering:
    • Overhead watering, especially with a heavy stream, can disturb the delicate microgreens and increase the risk of diseases. If using a watering can, use a rose attachment for a gentler flow.
  • Water in the Morning:
    • Water your microgreens in the morning to allow excess moisture to evaporate during the day. Avoid watering late in the evening to reduce the risk of fungal issues.
  • Prevent Water Splashing:
    • Minimize water splashing onto the leaves. Wet foliage for extended periods can encourage the development of fungal diseases.
  • Adjust Watering Frequency:
    • The frequency of watering depends on various factors such as temperature, humidity, and the specific needs of the microgreen variety. Adjust your watering schedule based on these factors.

By following these watering guidelines and paying attention to the specific needs of your microgreens, you can promote healthy growth and optimize their flavor and nutritional content.

3. Air Circulation for Care of Baby Microgreens:

  • Promote Airflow: Ensure good air circulation around the baby microgreens. This helps prevent the development of mold and ensures the exchange of gases necessary for photosynthesis.
  • Remove Humidity Covers: If you used a humidity dome or cover during the germination phase, remove it once the majority of seeds have sprouted to allow for better airflow.

Air circulation is important for microgreens to promote a healthy growing environment, prevent issues like fungal diseases, and ensure proper exchange of gases for photosynthesis. Here are some tips on providing adequate air circulation for microgreens:

Tips for Providing Air Circulation:

  • Gentle Approach: The goal is to provide a gentle and consistent airflow. Avoid strong winds or gusts that can damage the delicate microgreens.
  • Observe Seedlings: Pay attention to how your microgreens respond to air circulation. Adjust the fan settings or placement based on the seedlings’ growth and appearance.
  • Consistency is Key: Maintain consistent air circulation throughout the entire growth cycle to support the healthy development of microgreens.
  • Position a Fan: Use a small, gentle fan placed near your microgreens. The fan should provide a gentle breeze without causing damage to the delicate seedlings. Ensure it’s not directly blowing onto the plants, as this can lead to drying out.
  • Adjust Fan Speed: Low to Medium Speed: Set the fan to a low to medium speed to avoid excessive air movement. The goal is to create a gentle breeze that helps strengthen the microgreens’ stems without causing stress.
  • Fan Schedule: Regular Intervals: Run the fan at regular intervals, ideally for several hours each day. Continuous, gentle air circulation helps prevent the development of stagnant air pockets around the plants.
  • Rotate Trays Regularly: If you have multiple trays of microgreens, rotate them regularly. This helps ensure that all sides of the trays receive adequate air circulation, preventing uneven growth.
  • Ensure Ventilation in Indoor Spaces: If you’re growing microgreens indoors, ensure proper ventilation in the room. Good overall air circulation in the growing space can contribute to a healthier microgreen environment.
  • Natural Ventilation: If growing in an outdoor space or a greenhouse, take advantage of natural ventilation by opening windows or doors. This helps prevent the buildup of stagnant air.
  • Maintain Humidity Levels: Adequate air circulation can help control humidity levels. While microgreens generally prefer higher humidity to improve germination rate, it’s important to strike a balance and avoid excessive moisture that can lead to diseases.
  • Air Circulation to Prevent Fungal Issues: Proper air circulation is a great way to reduce the risk of mold and mildew in the growing medium and on the plants. These issues are more likely to occur in environments with poor airflow and high humidity.
  • Monitor Microgreens: Regularly observe the health of your microgreens. If you notice any signs of stress, such as wilting or discoloration, adjust the fan settings or improve overall ventilation.
  • Air Purifiers: In indoor growing environments, you may consider using air purifiers to improve air quality. These devices can help filter out impurities and enhance overall air circulation.

By incorporating these practices, you can create a favorable environment for your microgreens, promoting strong and vibrant growth while minimizing the risk of common issues associated with poor air circulation.

4. Temperature:

Microgreens generally thrive in a moderate temperature range, and the optimal temperature can vary slightly depending on the specific type of microgreen. Here are some general guidelines for the temperature range that microgreens prefer:

  • Maintain Optimal Temperature: Keep the growing environment at a consistent temperature between 60°F to 75°F (15°C to 24°C). Avoid extreme temperature fluctuations, which can stress the seedlings.
  1. Growing Stage:
    • As the microgreens progress to the growing stage, a slightly cooler temperature range is suitable. Aim for temperatures between 60°F to 75°F (15°C to 24°C) during this phase. This range allows for steady growth without excessive stretching or bolting.
  2. Colder Microgreens:
    • Some microgreens, like those from cooler climates or with a preference for cooler conditions, may tolerate temperatures on the lower end of the range. For example, certain varieties of lettuce or kale microgreens may do well in slightly cooler environments.

Tips for Maintaining Optimal Temperatures:

  • Use a Thermometer:
    • Install a thermometer in the growing area to monitor temperatures regularly. This helps ensure that the environment remains within the preferred range for microgreens.
  • Adjust Growing Spaces:
    • If growing microgreens indoors, position them near a window or use grow lights to provide adequate light and maintain the desired temperature range.
  • Avoid Temperature Fluctuations:
    • Microgreens are sensitive to sudden temperature fluctuations. Try to maintain a relatively stable environment to prevent stress on the plants.
  • Heating Mats (Optional for Care of Baby Microgreens):
    • In cooler climates or during colder seasons, consider using heating mats designed for seed starting to provide gentle warmth to the growing medium. This can help maintain optimal germination temperatures.
  • Ventilation:
    • Ensure proper ventilation to prevent temperature buildup. Stagnant air can lead to temperature variations, so use fans or natural ventilation to maintain consistent conditions.
  • Observation and Adjustment:
    • Regularly observe the health and growth of your microgreens. If you notice signs of stress, such as leggy growth or discoloration, adjust the temperature and other environmental factors accordingly.

Keep in mind that specific microgreen varieties may have slight variations in their temperature preferences. Therefore, it’s beneficial to familiarize yourself with the specific requirements of the microgreens you are growing. By maintaining an appropriate temperature range, you can support healthy and vigorous growth throughout the microgreens’ life cycle.

5. Scouting:

Scouting is simply observing your own microgreens as they grow into young plants. As you know, it doesn’t take long for microgreens seeds to grow into salad greens that are ready to eat. For that reason, you should scout your plants and monitor growth daily. 

  • Monitor Growth: Regularly check the microgreens for signs of maturity. You should also be checking for:
    • Problems with the growing medium. Spot any disease or mold issues. 
    • Noticing if there’s too much water or not enough water. Make sure your trays have good drainage.
    • Any damage or discoloring to the leaves. 

By checking your microgreen trays every day, you’ll be able to spot problems before they become disasters. 

6. Thinning (Optional for Care of Baby Microgreens):

  • Thin Seedlings: If you planted your seeds densely, consider thinning the seedlings once they have grown a bit. This allows for better airflow and prevents overcrowding, reducing the risk of disease.

Thinning microgreens is a common practice to ensure proper spacing and prevent overcrowding, which can lead to competition for nutrients, water, and light. Use clean and sharp scissors or shears for precise cutting without damaging nearby seedlings.

Here’s a step-by-step guide to thinning microgreens:

Steps to Thin Microgreens:

  1. Wait for Initial Growth:
    • Allow the microgreens to grow for a few days after germination. Once they develop their first set of true leaves and reach a height of about 1 to 2 inches, it’s time to thin them.
  2. Identify Overcrowded Areas:
    • Identify areas where the microgreens are too densely packed. Overcrowded sections can lead to stunted growth and poor air circulation.
  3. Choose Which Seedlings to Keep:
    • Decide which seedlings to keep based on their health, size, and vigor. Choose the strongest and healthiest-looking seedlings, and remove the weaker ones.
  4. Cut at Soil Level:
    • Using a sharp pair of scissors or small shears, carefully cut the undesired seedlings at soil level. Hold the excess seedling between your fingers and make a clean cut. Avoid pulling or yanking, as this can disturb the roots of nearby seedlings.
  5. Maintain Spacing:
    • Aim to leave an appropriate spacing between the remaining seedlings. This spacing allows each microgreen to access sufficient light, nutrients, and airflow.
  6. Dispose of Thinned Seedlings:
    • Dispose of the thinned seedlings. You can add them to your compost pile if they are disease-free.
  7. Water After Thinning:
    • After thinning, water the remaining microgreens gently. Thinning can be a bit stressful for the plants, and providing moisture helps them recover.
  8. Repeat as Necessary:
    • Repeat the thinning process as needed, especially if the microgreens continue to grow and become more crowded over time.

Tips for Thinning Microgreens:

  • Thin Gradually:
    • If you sowed densely, consider thinning gradually over a few sessions. This approach helps you gauge how the remaining microgreens respond and allows for adjustments.
  • Observe Seedling Health:
    • Regularly observe the health of the microgreens. If you notice signs of stress, such as yellowing or wilting, it may indicate the need for additional thinning or adjustments to growing conditions.
  • Thinning Frequency:
    • The frequency of thinning depends on the growth rate of the microgreens and the specific variety. Some microgreens grow rapidly and may need more frequent thinning.
  • Experiment with Seeding Density Next Time:
    • Through experimentation, you can determine the optimal seeding density for the specific microgreen varieties you are growing. Adjustments may be needed based on factors like light intensity and temperature.

By practicing careful thinning, you help create an environment where each microgreen can thrive and reach its full potential.

7. Fertilization (Optional for Care of Baby Microgreens):

  • Supplement Nutrients: While microgreens derive nutrients from the seeds initially, you may consider supplementing with a diluted, balanced liquid fertilizer. Apply sparingly, as microgreens have a short growth cycle.

Tips for Successful Care of Baby Microgreens:

  • Consistency is Key: Maintain consistent growing conditions, as fluctuations in light, temperature, or watering can stress the microgreens.
  • Scouting: Regularly observe the health of your microgreens. Address any issues promptly to ensure a successful harvest.

By following these care guidelines, you’ll nurture healthy and flavorful microgreens from their baby plants stage all the way to harvest. The best way to grow anything is to be proactive, look for signs of trouble and follow the best practices listed above. Very soon, you’ll be well on your way to harvest microgreens for your own personal use. 

Happy Growing!