Ruby Beets Microgreen Seed

Beets are a popular microgreen for their vibrant red and pink stems. At the same time, they are the nemesis of many commercial growers, holding strongly onto their hulls as they grow and showing inconsistent growth habits between varieties. Growers also report wildly different growing methods, making it difficult to know what the best approach to growing them might be for new growers.

Microgreen Soil

Like most microgreens, Beet shoots benefits from a well-drained, nutritious soil consisting of:

• Peat or coir for rooting and holding water (75%)
• Perlite or vermiculite for drainage and aeration (20%)
• Small amount of high-quality compost for nutrition (5%)
• Lime to neutralize pH

Many sources state that microgreens do not need nutrients to grow as they have “all the nutrients they need already in the seed”. Our experience is that microgreens grow better with additional soil nutrients, which can be provided with a small amount of compost in your soil mix. Good-quality compost also adds microbial life which can help reduce crop disease. However, too much compost, especially nutrient-rich compost like worm castings, can result in surface mold and reduced water uptake due to nutrient salt content.

Sanitizing Microgreen Seeds

Sanitizing your Beet seed helps reduce the likelihood of human pathogens in your crop. Zerotol is a peracetic-acid-based sanitizer which is approved for organic use in Canada and the United States.

Beet is a small seed and can be sowed wet or dry, depending on whether or not you have soaked the seed.

Beet seed can be sanitized by one of three methods, depending on whether or not you soak the seed:

1. Immersion: the seed is rinsed, immersed in a sanitizer solution, then sown while it is still wet.
2. Immersion then dry: the seed is sanitized by immersion in sanitizer then dried before sowing. The immersion method ensures the seed is fully engulfed in sanitizer to improve its efficacy. This is an effective but tedious process.
3. Spray after sowing: the seed is sanitized after sowing. This method only exposes one side of the seed to the sanitizer so is less effective than the immersion method.

Sowing Microgreen Seed

If you do not soak your beet seed, sow them using the “sprinkle” method, where the seeds are sprinkled evenly across the soil surface. The sprinkling can be done by using a “shaker”, a small handled sieve, or even a small jar or cup - everyone has their preferred method. Important in sowing the seeds is to get good coverage with the sprinkle as the seed cannot easily be redistributed once it is on the soil surface. Make several passes while sprinkling the seed lightly instead of trying to get the distribution perfect in one heavy pass.

If you soak your beet seeds, sow them using the “dump and spread” method:

• Measure out the desired volume of wet seed needed to sow a tray
• Do your best to “sprinkle” the wet seed around the tray
• Spread the seed evenly around the tray using your hands

This method can feel clumsy at first, but most growers establish a good technique for quickly and evenly spreading the seed. Even seed distribution is crucial for uniform crop growth. Avoid bare spots and seed clumping.

Germination

The germination stage can set the crop up for success or failure. Poor germination can be difficult to recover from, so optimizing germination conditions is crucial for crop success. Good airflow in your grow space is important for good germination with beets as they are susceptible to damping off. Also make sure the soil is not so wet when they go into the germination stage. Using a biologically active soil might benefit beets and reduce the likelihood of damping off during germination.

Beet shoots germinate well in the range of 75°F to 80°F (24°C to 28°C).

Stacking Sowed Trays

Beet shoots do well when “stacked” during germination, where trays are stacked one on top of the other.

For stacking beet shoots:

• Stack to a maximum of 3 trays high to prevent toppling - also reduces pressure on the bottom tray
• Top the stack with an empty tray and a 14-lb concrete paver

The top tray will have slightly taller growth than the bottom tray, but come harvest time they will almost completely even out

Uncovering Beet Microgreens

Beet shoots should be removed from the germination stage when the shoots are about ½ to one-inch tall and pushing up the cover tray on top of it. Beets do not have strong stems so will not push up their covering trays as easily as other crops do.

Water beet shoots thoroughly from above when removing them from the germination stage and moving them to the light.

Lighting

Beet shoots thrive in 14 to 16 hours of light at 5000K to 6500K, or in natural light. If using LED or fluorescent lights, keep them close enough to the crop to prevent stretching. How close will depend on the intensity of your lights. Online information shows a wide range of optimum PPFD values for microgreens production, ranging from 50 to 400 (Liu et al., 2022; MechaTronix, 2023). We have had success with beets with PPFD values as low as 25.

Watering

Avoid overhead watering of beet shoots after the initial watering.

Many growers like to water their crops using the “flood” method, allowing the soil to absorb water from below instead of from above. This method keeps the crop dry, which can reduce disease pressure and make for easier harvesting. Place a solid tray below your growing tray and fill that solid tray with water. How much water you add will depend on how dry the crop is and takes some time to master. Do not overwater as waterlogged (saturated) soil is at higher risk of contributing to crop disease.

Harvesting Beet Microgreens

Beet shoots are an easy crop to harvest and process. By keeping beet shoot leaves dry in the last 24 to 36 hours of growth they can be harvested and placed right into their packaging.

Cut beet shoots close to the base of the stem with a sharp, good-quality knife. Do not use scissors as this will tear the base of the stem and reduce storage time. Beets do not have a firm stem, so be gentle when cutting. Cut small sections at a time with a quick motion with the knife to ensure a good quality cut.

Packaging

Because of their delicate nature, beet shoots will do well to always be packed in a clamshell container. As a basic rule, aim for 8 oz in volume with your container for every 1 oz weight of your product.

Storing Beet Microgreens

Like most microgreens crops, Beet shoots should be kept dry and stored in a fridge between (2° to 4° C or 25° to 39° F) at all times. Be sure to maintain the cold chain during transport by using coolers with ice or a refrigerated vehicle.

Modern Grower Research

At Modern Grower we are constantly doing microgreens trials to better understand crop growth characteristics in varying conditions. All the data we provide is informed by our research.

Check out our ongoing research here to get a better understanding of the crop.