How much microgreen seed do I need per tray?

It depends on seed size and variety. As a guide, fine seeds such as broccoli, kale and amaranth need roughly 8 to 18 g per standard 10x20 inch tray, radish, beet and chard around 25 to 35 g, and large soaked seeds like sunflower, pea, corn and wheat 90 to 250 g. Select your variety in the calculator for the exact figure for your tray size.

How do professional growers decide on seeding density?

Pros standardise a target weight per 1020 tray for each variety, then trial small adjustments and log germination, canopy uniformity, harvest weight and mould pressure. The goal is a repeatable result every cycle; consistency batch to batch matters more than chasing one perfect number.

Should I weigh seed or measure it by volume?

Weigh it. At any production scale, weight in grams is the only repeatable unit; a level scoop drifts with seed size, moisture and lot. Use the volume estimate only as a rough field check and calibrate everything to a digital scale.

Can I push density higher to increase yield?

Only up to the canopy carrying capacity. Beyond it you trade yield for trapped humidity, weak leggy stems, uneven harvest and mould. If you run higher rates, back them with strong airflow, clean water and good light, and prove it on a few trays before scaling.

Why do my results differ from the chart?

Thousand-grain weight, germination rate, substrate, water and climate all shift the ideal rate between rooms and even between seed lots. Treat our figures as a calibrated baseline and fine-tune by 10 to 20 percent to your own conditions.

Do I need to soak the seeds first?

Large seeds such as sunflower, pea, fava, corn, wheat and chickpea germinate faster and more evenly after an 8 to 12 hour soak. Most small seeds are sown dry. Never soak mucilaginous seeds such as basil, cress, rocket or chia, as they turn to gel.

What is the blackout period, and does density change it?

Blackout is the initial dark phase that lets seed root and shoots stretch before they meet light. Denser sowings, and stacked or weighted trays, sometimes need a touch longer blackout for an even push. Lift the cover once stems are pale, tall and uniform.

Which varieties are best to start with?

Broccoli, radish, pea shoots, sunflower and kale are fast, forgiving and high-yielding, the reliable core most professional trays are built on. Slower herbs like basil, coriander and parsley are best added once your routine is dialled in.

microgreen seeds for reliable growing

Microgreens Seed Density Calculator

Pick a variety, enter your tray size, and get the exact seed weight, soak time, blackout days and expected yield — for any tray, across all 75 Deliseeds varieties.

1 · Choose your microgreen

No varieties match “{{ query }}”.

2 · Your tray size

Length

× Width

Measure the planted soil area, not the tray rim · {{ areaLabel }}

3 · How many trays?

You'll need

{{ r.grams }} g

of {{ sel.name }} seed per {{ areaLabel }} tray

≈ {{ r.volume }} by volume (use a scale for accuracy)

Soak

Blackout

To harvest

Est. yield

{{ r.yieldTray }} g / tray

Shop {{ sel.name }} seeds Browse all ~100 varieties at Deliseeds →

Plan by harvest

I want

of {{ sel.name }} → {{ r.traysNeeded }}

Recommended starting points for a standard 10×20″ (1020) tray, scaled to your dimensions. Blackout assumes trays are covered under light weight — our standard for even, vigorous growth. Seed size varies by batch — fine-tune after your first grow.

three quick steps

How to get your number

Measure your tray

Measure the planted soil area in cm or inches — length × width. Skip the rim; only the growing surface counts.

Pick the variety

Every microgreen has its own ideal density. Choose from 75 varieties — soak, blackout and harvest times come with it.

Weigh & sow

Use the gram figure (or the spoon estimate) for an even, healthy carpet — no overcrowding, no mould, no waste.

the full chart · 75 varieties

Seed density chart · every variety

Grams per standard 10×20″ tray. Tap a column to sort, filter by flavour, or ★ star your favourites and print your own chart.

	Variety{{ nameArrow }}	Density{{ densityArrow }}	Soak{{ soakArrow }}	Blackout{{ blackoutArrow }}	Harvest{{ harvestArrow }}	Yield{{ yieldArrow }}
	{{ row.name }} {{ row.flavour }}	{{ row.density }} g	{{ row.soak }}	{{ row.blackout }}	{{ row.harvest }}	{{ row.yieldL }} g	Buy →

No varieties match your filters.

Showing {{ rowCount }} of 75 varieties · ★ star the ones you grow, then “Print chart” for a clean grow-room copy

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Density

{{ card.density }} g

Harvest

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built for serious growers

Seeding density is where professional microgreens are won

Ask any commercial microgreen grower what separates a clean, sellable tray from a mouldy write-off and seeding density comes up first. It sets canopy uniformity, airflow, mould pressure, stem strength — and ultimately your yield and margin per tray.

We grow and supply at scale, and we work with professional microgreen farms, chefs and wholesale customers across Europe. The rates in this tool are the ones we trust in our own production — shared so you can hit a clean result on the first tray instead of the tenth.

Why density is a grower's first lever

Below the ideal rate you leave yield, light and shelf space on the table. Above it, seedlings compete for air and light, humidity gets trapped in the canopy, and damping-off and mould move in — the fastest way to lose a crop in production.

Dialling density per variety is the cheapest, highest-leverage control you have over quality, consistency and cost per tray.

How we calibrate every figure

Each rate starts on our own trial benches: we weigh seed to the tenth of a gram, sow replicate 10×20″ trays, and track germination, canopy density, harvest weight and quality.

We then cross-check against feedback from the commercial growers and chefs we supply, and review the numbers as new seed lots arrive. The result is a baseline you can actually build a production schedule on.

Why growers rely on this calculator

Save seed & money

Weigh out exactly what each tray needs — no over-sowing, no half-used packs. At today's seed prices, precise density is real money saved every cycle.

Higher, even yield

Hit the canopy density that fills the tray edge to edge, so every gram of seed pulls its weight at harvest.

Less mould & waste

Avoid the over-sowing that traps humidity and triggers damping-off — the number-one cause of failed trays.

Plan your production

Know seed weight, soak, blackout and harvest time up front, so you can schedule sowings and hit delivery dates with confidence.

What changes the ideal rate

No single number is right for every grow room. Treat our recommendation as a calibrated baseline and tune it to your own conditions. The biggest variables:

·Seed size & lot — thousand-grain weight drifts between harvests, so the same volume weighs differently from batch to batch.

·Germination rate — fresher, higher-vigour seed lets you sow a touch lighter for the same finished canopy.

·Substrate & depth — soil, coir or hydroponic mat, and how level it is, change how evenly seed settles and roots.

·Climate & airflow — temperature, humidity and ventilation decide how much density a tray can carry before mould.

A calibrated baseline, not a hard rule

Because of all the above, treat these figures as a trustworthy starting point rather than an exact prescription — weigh accurately, sow once, log the result, and fine-tune by ±10–20% to your setup. This calculator is built and maintained by Deliseeds, a trusted microgreen seed supplier to home and professional growers across Europe and beyond — ~100 conventional and organic varieties, every pack untreated, non-GMO and germination-tested.

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Seed density, explained

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