Last season one of our clients from the Khmelnytskyi region delayed a fungicide treatment by 8 days — because he was busy and waiting for suitable weather. The loss on the ear came to about 25%. We’re not telling you this to scare you — just to show that the window for fungicide protection in wheat really is narrow. 3–5 days — and the moment has passed.
Further on in the article — when exactly to go out into the field, which diseases are most dangerous in May and what happens if you’re late. And at the end — how we can help you go out at the right time.
Why timing is so important
A fungicide protects the plant only while the disease hasn’t developed yet or has only just appeared. If you wait for visible signs of infection, the product no longer gives the same effect. You’ve spent the money, but the yield has suffered anyway. The agronomic logic is simple: protection is preventive, not curative.
Optimal treatment timing (by BBCH stage)
- Tillering (BBCH 25–30) — the first preventive treatment: powdery mildew, brown rust
- Stem elongation (BBCH 32–37) — the main fungicide treatment of the season, the most important
- Flag leaf (BBCH 37–39) — if needed, under high infection pressure
- Heading (BBCH 51–59) — protecting the ear against fusarium and septoria of the ear
The window for each treatment is 3–5 days. Being late reduces the product’s efficacy by 30–50% even with a correctly chosen fungicide.
The main wheat diseases in May
More about protection products for each disease in our crop protection catalog.
Powdery mildew
A white powdery coating on leaves and stems, active in damp, cool weather. Reduces assimilation and weakens the plant
Brown leaf rust
Orange pustules on the leaves, spreads in warm, dry weather. With severe infection — losses of 20–40%
Septoria leaf blotch
Brown spots with a yellow halo and black pycnidia, gradually destroying the leaf apparatus
Septoria glume blotch
Infection of the ear at the milk stage, reduces grain weight
Fusarium head blight
A pink coating on the ear, reduces quality (mycotoxins) and grain weight
Yellow rust
Yellow stripes on the leaves, dangerous in a cool, wet spring
What to do if the deadline has slipped a little
If you see the first signs of disease, it’s not too late. A fungicide in curative mode gives 50–70% efficacy. That’s worse than prevention but better than nothing. The main thing is not to delay any longer. We can arrange a visit within 24–48 hours of your request.
Why application quality matters
The efficacy of a fungicide 40% depends on application quality — this isn’t an exaggeration but an agronomic fact. The right droplet size, even coverage of the leaf surface, treatment at the right time of day — all of this affects the result.
A self-propelled sprayer with a 36 m boom provides:
- Even coverage of the leaf surface — 95%+ effective contact area
- Accurate dosing in line with the product manufacturer’s label
- Treatment in the morning and evening hours — at optimal air temperature and humidity
- Minimal soil compaction between rows — preserving field structure
- Output of up to 200 ha/day — so as not to miss narrow deadlines
Products
We don’t push specific products — you can use your own. But if you need advice on choosing a fungicide for your situation, we’ll help. The current range of crop protection products is in our catalog.
Wester services — spraying wheat
We provide fungicide protection of wheat in the Khmelnytskyi, Ternopil, Vinnytsia, Rivne and Zhytomyr regions. Self-propelled sprayer, arrival within 1–3 days, from 400 ha, approximate price from $11/ha (operator and fuel included).
Logistics and terms for difficult or irregular fields are discussed separately.
- 10 years of work in the fields of Podillia and neighbouring regions — we know the specifics of local soils and crops
- Our own modern machinery — no middlemen, direct responsibility for quality
- Real arrival within 1–3 days — not a marketing promise but a commitment we keep
- A GPS report on completed work — transparency and control for the client
- Payment after the work is done — you pay for the result, not for promises
We’ll call you back within 2 hours and agree the visit.






















