★ Holy Grail · #1 choice in March Spring Pro, granular spring fertilizer

Lab-tested

Eurofins Belgium · 2025

PROFESSIONAL · GRANULAR · SPRING NPK 10-5-5+Fe

Spring Pro
cold-start fertilizer.

The first fertilizer of the year, working from 5 °C soil temperature. It wakes up colour and roots without a growth spike — for anyone who doesn’t leave spring to chance.

★★★★★ 4.9 412 reviews 97% recommend it

N · Nitrogen10%

P · Phosphorus5%

K · Potassium5%

+ Fe · Iron2%

Works from 5 °C soil temperature

Slow-release · 8–10 weeks of action

Deeper roots in 14 days

No burn risk (mini-prill)

Deep-green colour from chelated Fe

Pet-safe once watered in

Pack size Which size do I need?

Not sure? Start with our soil analysis, €49,95

Fast shipping1–3 working days in BE & NL

Money-back guaranteeno result in 30 days? Full refund

Made in Belgiumblended in Roeselare, lab in Antwerp

Pro formulaused on golf courses for 15 years

The Blend

Why exactly this composition.

A spring feed has to work in cold soil without causing lush growth later. So we lower the N, add Fe, and use coated prills for slow release.

Nitrogen, slow-release urea

60% coated (8–10 weeks). No peaks, no uneven growth. Works from 5 °C, long after fast-acting fertilizers have burnt out.

10%

Phosphorus, root start-up

Deliberately kept low (Flanders P limit). Just enough to bring the first root threads out of winter dormancy, no more.

Potassium, cell-wall strengthening

Sulphate form. Strengthens cell walls against late night frost and the shift to drier weather. Chloride-free, better for soil life.

Iron, chelated (EDDHA)

The secret sauce. Delivers the deep-green colour you see on golf courses without turning black or staining paving.

Packaging UV-resistente HDPE · recycle 1

Application

Spread now, plan the rest of the year.

Spring Pro is the first of four. Combine with Equilibrium Pro (summer) and Autumn Pro (autumn) for a lawn that stays in shape 12 months a year.

01 · NOW

March, April

30 g/m² 8–10 wks

Spring Pro · this product

Spread on dry grass at soil temperature ≥ 5 °C. Water within 48 h or wait for rain. First greening after ±10 days.

May, June

25 g/m² 6–8 wks

Equilibrium Pro

Keeps growth steady without a surge. Boosts drought tolerance and rooting for the hot months.

August

20 g/m² Liquid

RootGrow Liquid

A liquid boost after heat stress. Drives recovery and preps the lawn for the autumn feed.

October

35 g/m² 10–12 wks

Autumn Pro

High K, low N. Makes the grass winter-hard. Drives roots deep, spares top growth.

Lab tip measure soil temperature at 5 cm depth before the first spread. Below 5 °C the grass is still waiting. Above 8 °C the timing is perfect.

Specifications & comparison

Read the label, not the marketing.

Full transparency about what’s in the bag. We publish every batch online, with batch number and analysis date.

NPK + Fe10-5-5+2

Granule formMini-prill (1.4–2.2 mm)

Duration8–10 weeks slow-release

Dosage30 g / m²

Min. soil temp.5 °C

Pet-safeOnce watered in, ±2 h

Coverage 10kg≈ 300 m²

Shelf life36 months

Feature

Spring Pro

Garden-centre brand

DIY-store feed

Works from 5 °C

Slow-release coating

60% coated

30%

Chelated iron

EDDHA

Sulphate

Lab report per batch

Price / m²

€0,17

€0,21

€0,11

Lab, Batch SP-2025-03

The analysis, literally from the lab.

Every batch is independently analysed by Eurofins Belgium, released before production. Click through for the full PDF.

Eurofins Agro Belgium

Report #BE-2025-04812 · 04/03/2025 · Antwerp

VALIDATED

Stikstof (N)total · slow-release

10.04%

Fosfor (P₂O₅)water-soluble

5.12%

Kalium (K₂O)sulphate

5.21%

IJzer (Fe)EDDHA chelate

2.08%

Magnesium (MgO)trace element

1.04%

Full report includes heavy metals (Cd, Pb, Cr, Ni, Hg), all within EU limits.

Download PDF (3.2 MB)

What customers say

412 reviews. 97% recommend it.

Verified purchases, no filters. We show the less positive reviews too.

Jeroen V.

Verified Antwerp · 12 days ago

★★★★★

Finally a feed that already works in March.

10 days after spreading I already saw a difference — deeper colour, no lush growth. I used to use a garden-centre brand that only kicked in by May. Spring Pro is a class above.

10kgClay soil500m² lawn

Sofie M.

Verified Ghent · 3 weeks ago

★★★★★

Really belongs with the soil analysis — buy them together.

Had the soil analysed first; the advice was Spring Pro + extra iron. Result after 3 weeks: my neighbour’s lawn now looks spray-painted by comparison. My wife has newfound respect for me.

20kgSandy loamWith soil analysis

Dieter P.

Verified Roeselare · 1 month ago

★★★★☆

Works as promised; faint ammonia smell in week 1.

The effect is excellent; I take off one star for the smell in the first 5 days after spreading. Not unpleasant, but noticeable. After that it’s gone. Otherwise a top product.

10kgClaySecond purchase

Tom C., Greenkeeper

Verified Knokke · 2 months ago

★★★★★

A pro formula that really works for pros.

I’ve worked on golf courses for 18 years and now use Spring Pro at home too. The granule size is uniform, no clumping, no dust. The mini-prill disappears completely into the grass after the first rain. Five stars.

20kgPro use5th order

See all 412 reviews

Mixing ratios

Precise dosages & tank-mix.

Liquid elixirs: 200 ml per 10 L of water covers 100 m². Spring Pro works dry — spread without mixing, but combine it with the elixirs below.

1 Base dosage

Granular (this one)30 g/m²

Liquid elixir200 ml / 10 L

Coverage per bottle100 m² · 5×

Pressure sprayer2–3 bar

2 Tank-mix combinations

Essential + Rootgrow + Volume — tank-mix together
Shield + Silicium — climate guard mix
Shadow + Wetting — for shade and dry zones
Colour Elixir — always spray solo
7-day wait between granular and liquid

Combine with these elixirs for the best result

★ Recommended partners

PERFORMANCE · ELIXIR

Rootgrow Elixir

30-50% faster root growth in 3 weeks — a seamless follow-on to the Spring Pro start.

200 ml / 10 L · NPK 8-6.5-1.5€27,00

HOLY GRAIL · ELIXIR

Essential Elixir

Irish seaweed biostimulant — stress survival and overall vitality. Safe with all granulars.

200 ml / 10 L · zeewier€28,00

PERFORMANCE · ELIXIR

Shield Elixir

20% K hardens cell walls — apply 2 weeks after Spring Pro for heat/drought resistance.

200 ml / 10 L · 20% K€26,00

Frequently asked questions

Answers before the first spread.

From what temperature can I spread Spring Pro?

Soil temperature at 5 cm depth ≥ 5 °C. In Belgium you usually reach that from mid-March. A cheap soil thermometer costs €10. Too cold? The granules won’t dissolve and stay visible for a week or two — they’re not lost, they just don’t act yet.

Do I need a spreader or can I do it by hand?

For < 100 m² by hand is fine — mentally divide the lawn into 1 m strips and throw 30 g/m². Above 100 m² we strongly recommend a spreader (we sell one, or borrow your neighbour’s). Uneven spreading causes stripes.

Will it burn my grass in drought?

Mini-prill + 60% slow-release coating makes burn risk very low. But: never spread on dry grass without rain or irrigation within 48 h. The coating needs moisture to start.

Safe for children and pets?

Yes, once watered in (about 2 hours after good rain or irrigation). Keep them inside during spreading. The granules aren’t toxic, but can cause an upset stomach if eaten, so just wait until they’ve settled into the soil.

Does it work on mossy or neglected lawns?

Spring Pro itself doesn’t kill moss. For moss, use our RootGrow Liquid + scarifying. A week after scarifying is the ideal moment to spread Spring Pro on the weakened lawn — a kickstart for recovery.

Can I combine it with your soil analysis?

Strongly recommended. Our soil analysis (€49,95) gives you the exact dosage — on some soils 25 g/m² is enough, on others 35 g/m². It often saves you more than the price of the analysis itself.

Spring Pro
cold-start fertilizer.

Why exactly this composition.

Spread now, plan the rest of the year.

Read the label, not the marketing.

The analysis, literally from the lab.

412 reviews. 97% recommend it.

Finally a feed that already works in March.

Really belongs with the soil analysis — buy them together.

Works as promised; faint ammonia smell in week 1.

A pro formula that really works for pros.

Precise dosages & tank-mix.

Combine with these elixirs for the best result

Answers before the first spread.

Often bought together.

Not sure which fertilizer you need? Take the lawn quiz.

Spring Procold-start fertilizer.

Why exactly this composition.

Spread now, plan the rest of the year.

Read the label, not the marketing.

The analysis, literally from the lab.

412 reviews. 97% recommend it.

Finally a feed that already works in March.

Really belongs with the soil analysis — buy them together.

Works as promised; faint ammonia smell in week 1.

A pro formula that really works for pros.

Precise dosages & tank-mix.

Combine with these elixirs for the best result

Answers before the first spread.

Often bought together.

Not sure which fertilizer you need? Take the lawn quiz.

Spring Pro
cold-start fertilizer.