Introduction

Most microgreen farmers operate under similar conditions - indoors and climate-controlled. Despite having similar setups, everybody has their method for growing each variety. I’ll explain how I grow sunflower microgreens at my company, Piedmont Microgreens (PMG). We grow 400+ trays per week (TPW) at PMG, and 8% of those are sunflower. Here are the farm's parameters and the conditions for growing our microgreens. Yes, the relative humidity (RH) is high. I want the RH to be between 45-55%, but we’re working on it. Regardless, our crops grow well and we don’t have any issues with disease. We fertilize all crops with one dosing of dilute Ocean Solution. We dilute one ounce of Ocean Solution to a gallon of water. Every tray gets fertilized first thing out of germination. The rest of their life they get plain regular city water.

Avg. Farm Temperature	75°F/24°C
Avg. Farm Humidity (RH)	65-72%
Lights On	16 Hours
Lights Off	8 Hours
Shelf Spacing	10”
Lighting	2*T5 LEDs 22W/Shelf
Soil	Promix BX
Trays	1020 Shallow
Water	Municipal, Bottom Watering
Fertilizer	Ocean Solution

Growing Sunflower Microgreens

Sunflower microgreens or sunflower shoots are among the most common crops farmers grow because they are one of the most well-recognized by the public. Crops like pea shoots, sunflower shoots, and broccoli microgreens have been around the longest. Most consumers have seen or heard of them before. Sunflower shoots are popular with chefs as well. These reasons push new growers to add them as one of their first menu items. However, tons of microgreen varieties are easier to grow than sunflower shoots, such as broccoli and radish. Why? Quality sunflower seeds can be hard to find. Since practically every microgreen farmer grows sunflower shoots, the demand on the seed supply puts pressure on seed vendors to sell subpar seeds. Seed quality is always critical for microgreen farmers, but especially with sunflower shoots. Sunflower seeds are more susceptible to harboring dormant diseases and mold spores. Sunflower shoots are also one of the few crops with a seed hull that’s both tough and doesn’t fall off naturally. For example, the seed hulls of broccoli, cabbage, and kohlrabi are small and soft. They fall off naturally during the germination and grow-out phases. If they don’t fall off, they’re so soft you’d never know when eating the finished microgreen.

Growing sunflower shoots starts with soaking 120g of seed in a bucket of water overnight. Soaking starts germination and softens the seed hull for easier shedding later. Drain the seeds and spread them over a prepared 10”x20” tray of soil. Water the tray and then place a bottom tray under each planted tray. Stack your trays no taller than five to a stack. Place the stack on your germination rack, then put a 10 to 15# paver on top. Leave the sunflower in germination for three days. After three days, remove the sunflower trays from germination and spread them out under your grow lights. Water the trays as needed on day four. By day five, the sunflower shoots have unfurled and opened up enough that it’s now time to start working on shedding the seed hulls.

Wash your hands. You’re going to use your hands to remove a majority of the seed hulls prior to harvest. Flex your hand and fingers into a stiff board-like shape, like you’re going to slap someone. Flex your palm to make a slight curve. Your fingertips will be higher than your palm when viewed from the side. Brush your hand over the tops of the sunflower shoots. Imagine you’re trying to sweep your hand 1/4” below the crop canopy. The plants will flex and bend a little, but they won’t snap. If you push your hand any deeper into the canopy, you risk damaging the leaves. Brush your hand back and forth multiple times and listen as the hulls fall off and hit the floor. Repeat this brushing exercise on day six and seven. Harvest is on day eight or nine, just as the true leaves are starting to emerge. You should only be left with 5-10% of the seed hulls. It’s unlikely you’ll ever get a perfectly seedless crop at harvest.

Our aim at Piedmont Microgreens is to let no more than three seed hulls make it into a finished container of sunflower shoots. We do this by sorting through the harvested sunflower shoots before packing. We’ll harvest the sunflower shoots into a large bin, and then sort them from there. We’ll pull out and compost any sunflower shoots with damaged leaves or the hull still attached. This step is time-consuming and tedious, but it ensures a high-quality product. The tenacity of sunflower hulls is the reason many large-scale growers avoid growing this crop altogether. By "large-scale grower," I mean multi-million dollar operations that supply big retail grocery chains. It's hard to streamline and automate sunflower shoot production in these large operations. The seed hulls are tricky to deal with, no matter how high-quality the seed.

Product Size	Container Size	Price	Client Type
3 oz.	20 oz.	$3.50	Retail
4 oz.	32 oz.	$8.00	Restaurants
8 oz.	64 oz.	$14.00	Restaurants
8 oz.	64 oz.	$10.00	Wholesale

Preferred Supplier	Sungrown Organics or Greener Harvest
Preferred Variety	Black Oilseed
Sow Density	120g/Tray
Est. Seed Cost/Tray	$0.90 - $1.30 (Buying 25-50#s of Seed)
Est. Gross Margin/Tray	77% (Restaurants)
Popularity Level	9/10 (Top 5)
Difficulty of Growing	Moderate