Microgreens Educational Kit

IntroductionMicrogreens are young vegetables that are used both as an ingredient and a

visual/flavor component in fresh salads and fine dining. Microgreens are a growing

trend and it is easy to see why. They are easy and fast to grow, have significant

nutritional value, and are tasty. Arugula

Microgreens contain 48.5 mg of vitamin

C whereas their grown counterparts

contain only 15 mg, radish Microgreens

are said to be spicier and red cabbage

microgreens are reported to be sweeter

(Marcello, 2018). According to a 2012

research study in the Journal of

Agricultural and Food Chemistry, “In general, microgreens contain considerably

higher concentrations of vitamins and carotenoids than their mature plant

counterparts, although large variations were found among the 25 species tested. In

comparison with nutritional concentrations

in mature leaves, the microgreen cotyledon

leaves possessed higher nutritional

densities” (Gibson, 2016). Microgreens can

be grown almost anywhere, even during

winter. Because microgreens take so little

space, it is practical, and profitable, to grow

them indoors and in urban areas (Wallin, 2018). Because of their popularity they

Figure 1 Example of Microgreens

Figure 2 Example of Sprouts

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are a great product to market and sell year-round in both the home and the

classroom.

A common mistake made with growing these specialty crops is confusing

microgreens with sprouts. Sprouts are germinated seeds that are eaten root, seed

and shoot. Whereas sprouts are seeds that germinate by being soaked and rinsed in

water, microgreens are grown in soil, peat moss and like mediums (Gibson, 2016).

See Figure 1 and 2 for examples of each.

The purpose of this kit is to provide a fun and engaging way to involve

students in horticulture curriculum. Growing microgreens is an easy way for the

whole class to produce a product that can be sold to the community. Vegetable

production can be accomplished on both a large and small scale in urban areas

using raised beds, the classroom window sill, or greenhouses for year round

production. This kit will provide instruction, suggestions, and tips that will help

educators make an engaging project and a potential fundraiser.

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Table of Contents

Introduction............................................................................................................................1

Growers Guide........................................................................................................................4

Material Costs..................................................................................................................................4

Seed Selection..................................................................................................................................4

Sowing the Seeds.............................................................................................................................5

Watering your Microgreens.............................................................................................................6

Caring for your Microgreens...........................................................................................................7

Harvesting Guide....................................................................................................................8

How and When to Harvest...............................................................................................................8

Packaging, Handing and Shelf Life.................................................................................................9

Marketing Microgreens.........................................................................................................10

Safety Concerns....................................................................................................................11

Packaging Requirements...............................................................................................................11

Recommended Storage Conditions.................................................................................................12

Best Practices to Prevent Contamination and Disease....................................................................13

Recipes..................................................................................................................................13

References.............................................................................................................................16

Appendixes- Exposed URLs...................................................................................................18

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Growers Guide

Material Costs

The startup costs for microgreens are very low, all you will need is trays,

soil, seeds, water, sunlight (or sun lamp) and packaging if you plan to market and

sell the finished product. Table 1 shows estimated costs. Espiritu (2016) values the

cost of production to be $2-4 per tray. The highest cost being seed selection.

Seed Selection

There is no specific “microgreen seed” because the end product never

reaches maturity. Even melon seeds can be microgreen seeds. The seeds you use

should be untreated. Many markets that buy microgreens prefer organic because

they view microgreens as a premium product (Wallin, 2018). Seed selection is

based on taste and popularity. Popular and tasty seed selections include radishes,

arugula, red beets, sunflower, red radishes, cilantro, basil, green peas, popcorn,

red cabbage or mustard green seeds (Marcello, 2018). The same with any

Table 1 Retrieved from https://university.upstartfarmers.com/blog/how-to-grow-microgreens-beginners-guide

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garden project, some seeds are easier to grow than others. The best way to

determine what seeds are best for your classroom is to experiment by testing

them out both in ease of production and marketability. Checking the menus of

fine dining restaurants and seeing what is offered at farmer’s markets in the

local area can give you a good idea of what to try out first. An easy place to

start is with basil, arugula, radish, and sunflower. Another great idea is to find

seeds for salad mixes and specially selected microgreen mixes that combine

greens with similar growth rates, compatible flavors and beautiful coloring

including reds, purples and greens. Recipes for salads will be included later in

this guide. While Purdue University neither endorses nor discredits Johnny’s

Selected Seeds , they offer a variety of seeds and seed mixes that are great for

beginners. If you are reading this guide in a non-electronic format the exposed

URLs are included in the appendixes section. For a full detailed seed

comparison chart check out this resource from Johnny’s Selected Seeds .

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Sowing the Seeds

Unlike sprouts, microgreens will need some kind of medium to grow. To

sow your seeds, you will need a growing medium such as soilless mix or any high

quality potting soil, trays, and domed

lids. Microgreens are often sown into

standard 10x20” flats or 20-row seed

flats filled with a light, sterile, soilless

mix to a depth of 1½–2" (Johnny's

Selected Seeds, 2018). When sowing

your seeds, you will want to spread

them generously, thick enough to

cover the flat but not thick enough to

inhibit air flow to the seeds. Once sprinkled onto the soil gently tap in, do not

cover with soil, see Figure 3. As a rule of thumb, there should be 10-12 small seeds

per square inch and 6-8 large seeds per square inch (Johnny's Selected Seeds,

2018). The next step is to create a humid, warm environment that will spur

germination. You can do this by taking moistened paper towels and cover the seeds

and then place a clear plastic cover to trap heat inside. At the first sign of growth

(usually 3 to 4 days) remove the plastic cover and discard the paper towels

(Marcello, 2018).

Watering your Microgreens

Microgreens are somewhat delicate plants and because of this you must take

care in watering your plants. One strategy to keep your soil moist without harming

or drowning the seeds is to use a

spray bottle with a misting

nozzle. Penn State Extension

Figure 3 Retrieved from http://www.seattleurbanfarmco.com/blog/2016/11/7/encyclopedia-botanica-podcast-episode-21-microgreens

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recommends using “bottom watering” to keep your plants happy, see Figure 4.

Take a tray with no drainage holes and fill with an inch of water. Then place the

tray with drainage holes and your microgreens into the first tray and let the water

seep from the bottom of the soil up to the seeds (Marcello, 2018). Change or refill

your water tray every 2-3 days. This method also keeps plants cleaner as there is

no “splash back” on the plants that occurs from traditional watering techniques.

Utah State University Extension published a video tutorial that summarizes and

demonstrates both sowing seeds and watering techniques. Access that video

tutorial here.

Caring for your Microgreens

Whether you are growing in a greenhouse, a window sill or a pot you should

take into account soil temperature, humidity, lighting and succession planting. The

optimal soil temperature is 65-75 degrees Fahrenheit (Braunstein, 2018).

Temperatures higher than that can promote disease and fungi growth. Humidity

can be stimulated by using a cover over your trays during germination. Once the

seeds have sprouted, remove the cover and see that the air is circulated to reduce

the chance of disease. Air circulation is needed to keep plants healthy. Household

fans and normal greenhouse ventilation will be sufficient enough. While plants can

germinate without direct access to light they will need light to turn green. If you

are growing in the winter or indoors you will have to supplement natural light with

artificial light. Grow lights or lighting especially designed for plant growth will be

a good investment if you plan to grow on a large scale. If not, fluorescent bulbs put

out more light and less heat than regular lighting and are a more cost effective

option (Braunstein, 2018). Succession planting will be necessary if you plan to

grow on a large scale or for a restaurant. The time in which you plant will be based

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upon your seed variety and how much you wish to produce. We will discuss this

topic further in the harvesting section.

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Harvesting GuideHarvesting microgreens is relatively quick and easy. Most 10x20” trays

yield 8-12 oz. of product (Espiritu, 2016). Table 2 depicts estimated revenues is

included below. Recalling the information compiled in Table 1 you can see how

profitable growing this product can be if it is marketed correctly. As you learn your

market and what seeds sell the best you will be able to produce and sell more

plants.

How and When to Harvest

Microgreens should be harvested at

the first-true-leaf stage of growth, with

the cotyledons still attached, at heights

varying 1–2" (Johnny's Selected Seeds,

2018). Plants typically reach this stage

two to three weeks after planting but

varies depending on the variety of seeds

that were planted (Diehl, 2018). The

cotyledons are the first leaves to emerge

when a seed germinates because they are

Table 2 Retrieved from https://university.upstartfarmers.com/blog/how-to-grow-microgreens-beginners-guide

Figure 5 Retrieved from http://www.veggiegardener.com/what-are-a-vegetable-plants-true-leaves/

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a part of the plants embryo. They provide nutrients to the plant until the first true

leaves emerge. The first true leaves form above the cotyledons and will look more

like the mature plant, often different from the cotyledons. In Figure 5 you can see

the difference between the two types of leaves. Once your microgreens have

reached the optimal stage for harvesting simply cut the stems near the root and

place to the side, see Figure 6. Use very sharp, commercial grade shears (scissors)

to prevent bruising or tearing of the leaves. It is optional to next wash the cutting

by gently dipping into cool water and pat dry with paper towels. Investing in a

salad spinner to dry the greens is a smart idea if implementing this method. Try to

work speedily without crushing greens so the greens do not go unrefrigerated for

long if you plan to store for an extended amount of time.

Packaging, Handing and Shelf Life

You can sell microgreens as a rooted living product or cut and packaged in

plastic containers. Generic clam shell containers are cheap to obtain and prevent

the greens from being crushed. Handle your greens with care and sell immediately

for the best taste. If you cannot sell

immediately refrigerate your

microgreens. The shelf life of most

microgreens does not exceed 2-3

weeks refrigerated (Mir, Shah, &

Mir, 2016). Some growers find that

not washing the greens after

harvest and waiting till right before

use adds to the shelf life of this

highly perishable good. Planning

when to harvest and how much to

Figure 6 Retrieved from https://themicrogardener.com/wp-content/uploads/2013/03/Microgreens-snipping-with-scissors_wm.jpg

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harvest is very important to prevent waste. Remember to use safe handling and

clean hands when washing, storing and selling your product. Because of

microgreens relative novelty it is beneficial to package microgreens to where they

are easy to eat, even in premade salads or mixes. We will discuss this more in the

marketing section. Commercially, growers can produce 20-25 crops of

microgreens a year because of their short turn around (Wallin, 2018). Make sure to

develop a customer base before producing on that scale to avoid loss of money and

product.

Marketing MicrogreensFor all their benefits, Microgreens are still a highly perishable product. Most

growers recommend not harvesting more than you can sell in a given week. If you

are unable to sell out come harvest, there is always the option to let them keep

growing and sell them as baby greens in the next few weeks. Baby greens are just

older greens (45-60 days) that do not boast the superior nutrition benefits of

Microgreens but are still a bite sized, novelty product that should be relatively easy

to sell through the venues. Johnny’s Selected Seeds (2018) offers these guidelines

to help guide you when beginning to market your products.

Before you ramp up production explore your market opportunities and be

sure you have a customer base. Contact potential microgreens customers in

your projected distribution area — restaurants are the most common

channels, but specialty food stores and some farmers' markets may also have

demand.

Plan to produce a few preliminary mixes, or set up an assortment of

individual microgreens samples to offer free of charge, to develop your

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customer base. This approach can also be effective when introducing a new

variety or line of produce to established customers.

Give your brand pizzazz with a one-of-kind mix. First, choose a set of

candidates with an interesting complement of colors, flavors, and textures. If

you select 5–6 varieties with similar growth rates and cultural requirements,

you can combine equal or varying ratios of seed before sowing to produce

the mix. If you select varieties with different growth rates and/or cultural

requirements, you can seed them on separate days, grow them individually,

and have them ready for harvest at the same time, blending them together

after harvesting. In either case, be sure to keep detailed records of varieties,

seeding dates, and the percentages of each component used, so you can

easily duplicate a promising custom mix.

Finally, if you're not already routinely surveying your buyers and chefs for

input and feedback, add that to your checklist, too, so you can modify and

improve your product line over time. Customers stay more engaged when

offered novel varieties and combinations, especially when confident of the

freshness and quality of your product.

Safety Concerns Since Microgreens are so easy to grow indoors, pest control is not a major

concern unless you are producing on a large scale in a commercial greenhouse.

Keeping your product clean and at the right humidity is the best way to keep your

product safe. The bottom watering technique discussed earlier is a great way to

keep the greens clean. Watering the greens traditionally splashes soil onto the

leaves that will have to be cleaned off at harvest. Keeping your seeds covered is a

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beneficial practice to encourage sprouting but once sprouting has occurred,

covering plants increases the risk of mold.

Packaging Requirements

Purdue Extension recommends the following practices in labeling your

products:

Any packaged food sold at a farmers’ market that includes more than two

ingredients, including both ready to-eat and processed food, should have a label.

The label must provide the following.

The common name for the food product.

A list of ingredients if there are more than two, given in descending order of

predominance by weight.

Quantity specifications, given in weight, volume, or pieces.

The name and complete address of the business.

Claims such as “heart healthy,” “light or low fat,” or “sugar free” must be

substantiated by the nutritional facts on the label. It is acceptable, however, to

claim added or left out ingredients, such as including “no sugar added” on the

label.

For more information read Food Safety for Farmers Markets- Purdue Extension .

Recommended Storage Conditions

For small scale production, normal refrigeration is satisfactory. The best

storage temperature is below 40°F and above freezing. Freezing must be avoided.

Cool greens immediately after harvest. For temporary storage, a temperature of 34°

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to 36°F and a relative humidity of 90 to 95 percent is recommended. For the best

quality product store for a week or less covered with a damp towel. Long-term

storage is not recommended (Kasmire & Cantwell, 2017).

Best Practices to Prevent Contamination and Disease

For more safety information consult the Commodity Specific Food Safety

Guidelines for the Lettuce and Leafy Greens Supply Chain- FDA. This document

contains the recommended and voluntary practices for industry. Washing your

greens at harvest, using clean and secure packing materials, cooling immediately

after harvest, using clean water, planting with new potting soil, and reducing

humidity after sprouting are all best practices to keep greens safe.

Recipes

If you are selling microgreens at a farmer’s market or like venue it is

important to make your product easy to use and easy to understand. Instead of

selling a bag of greens, sell a “just add dressing” salad mixture in an attractive

packaging. Make it easy for yourself and plant green mixtures that taste great

together in the same container. Popular seed mixtures were discussed previously in

the “selecting seeds” section. Included below are some recipe ideas for producers

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to make ahead of time or handout paper copies with the raw product to give your

customers ideas on how to use your unique, nutritious product.

Figure 6: Retrieved from the Micro Gardener

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Figure 6: Retrieved from EverydayDishes.com

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ReferencesBraunstein, M. (2018). Warmth and germination. Retrieved from Mircrogreen

Garden: http://www.microgreengarden.com/warmth

Diehl, A. (2018). How to grow microgreens. Retrieved from Gardener's Supply

Company:

https://www.gardeners.com/how-to/how-to-grow-microgreens/7987.html

Espiritu, K. (2016, August 25). How to grow microgreens: The beginner’s guide.

Retrieved from Upstart University:

https://university.upstartfarmers.com/blog/how-to-grow-microgreens-

beginners-guide

Gibson, A. (2016). The micro gardener. Retrieved from Easy Guide to Growing

Microgreens : https://themicrogardener.com/easy-guide-to-growing-

microgreens/

Johnny's Selected Seeds. (2018). Guide to year-round microgreens production.

Retrieved from Johnny's Selected Seeds:

http://www.johnnyseeds.com/growers-library/vegetables/year-round-micro-

greens-production.html

Kasmire, R. E., & Cantwell, M. (2017). Postharvest handling systems: Flower,

leafy and stem vegetables. Retrieved from Vegetable Research &

Infromation Center- University of California Cooperative Extension :

http://vric.ucdavis.edu/postharvest/leaf.htm

Marcello, B. (2018, February 22). Growing microgreens. Retrieved from

PennState Extension: https://extension.psu.edu/growing-microgreens

Mir, S. A., Shah, M. A., & Mir, M. M. (2016, February). Microgreens: production,

shelf life, and bioactive components. Critical Reviews in Food Science and

Nutrition , 57(12), 2720-2736.

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Wallin, C. (2018). Top 10 questions about growing microgreens for profit.

Retrieved from Profitable Plants Digest:

https://www.profitableplantsdigest.com/top-10-questions-about-growing-

microgreens-for-profit/

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Appendixes- Exposed URLs

Johnny’s Selected Seeds

o http://www.johnnyseeds.com/vegetables/microgreens/microgreen-

mixes/

Microgreen Seed Comparison Chart

o http://www.johnnyseeds.com/growers-library/vegetables/micro-

greens-comparison-chart.html

Resource for Purchasing Soilless Mixes

o http://www.johnnyseeds.com/tools-supplies/seed-starting-supplies/

soilless-growing-mixes/

Utah State Extension Video Tutorial

o https://www.youtube.com/watch?v=deI1VyB-GsI

Food Safety for Farmers Markets- Purdue Extension

o https://www.extension.purdue.edu/extmedia/EC/EC-740.pdf

Commodity Specific Food Safety Guidelines for the Lettuce and Leafy

Greens Supply Chain- FDA

o https://www.fda.gov/downloads/food/guidanceregulation/

ucm169008.pdf

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