The key to success in a no till farming

One of the reasons why many farmers stick with ploughing is that turning the soil covers up mistakes – ploughing “forgives” a lot. However, the accumulation of years of mistakes beneath the surface eventually becomes visible, because problems cannot be swept under the rug forever.

By contrast, no till farming requires precision, attentiveness and careful selection of timing and tools. Although this demands effort, soil managed in this way rewards the farmer by revealing its full potential: rebuilding structure, increasing fertility, preventing degradation and improving yields.

Important! No till farming delivers benefits only when accompanied by good agronomic practices: maintaining continuous soil cover, a diverse and well-designed crop rotation, and avoiding soil compaction. The key to success is long-term care for soil fertility and structure – so that the soil becomes healthier year after year instead of poorer.

Continuous soil cover – cover crops and mulch all year round

One of the fundamental principles of conservation agriculture is: never leave soil bare. Exposed soil is vulnerable to erosion, drying out and loss of biological life. That is why, in a no till agriculture, maintaining continuous soil cover through cover crops and leaving residues as mulch is so important.

- Cover crops protect soil actively and biologically: they live and grow, and their root systems and biomass improve soil structure, bind nitrogen and protect against erosion. After vegetation ends (e.g. after winterkill), they remain in the field as plant residues or are shallowly mixed.

- Mulch protects soil passively and mechanically: it does not grow but lies on the surface like a blanket. A layer of dead plant residues left on the soil surface may come from the previous crop, terminated cover crops or straw.

Cover crops are additional plants grown between main crops, e.g. fast-growing mixtures sown after harvest and incorporated or winter-killed before spring sowing. Above all, they protect soil from erosion during periods when fields would otherwise be bare. Leaves and roots shield the soil from raindrop impact and wind. Even during heavy rainfall, soil under cover does not wash away or crust, because raindrops lose energy on plants and water infiltrates instead of running off. Fast-growing cover crops produce significant biomass – both above and below ground – which remains in the field. This fresh organic matter is decomposed by microorganisms, enriching soil with humus. It is estimated that a good green-manure cover crop can provide the equivalent of up to half a manure dose in terms of soil enrichment.

Diverse root systems penetrate soil layers at different depths, supporting aggregate (crumb) structure and creating root channels that improve aeration and water-holding capacity. After roots die, pores and humus remain, forming a sponge-like structure that stores water and allows roots of subsequent crops to grow deeper.

Tap-rooted plants (e.g. oil radish, sunflower, phacelia) penetrate deeply – even 1.5–3 m – loosening subsoil.

- Fine-rooted species (grasses, clovers) intensively exploit the topsoil layer.

Dense cover crop vegetation stimulates biological life: earthworms and microorganisms become more active under cover. Cover crops provide carbon and energy. Observations show that fields with cover crops host significantly more earthworms than bare fields. Earthworms consume residues, create channels and mix soil – effectively improving fertility (Darwin famously called them “nature’s ploughs”).

Finally, cover crops and mulch suppress weeds – green cover or residue layers limit light access and space for weed germination.

Crop rotation and crop diversity – the foundation of a healthy no till farming

In no till farming, crop rotation becomes especially important. Without the “sanitising” effect of ploughing, rotation prevents the build-up of crop-specific diseases, pests and weeds. Avoiding monoculture is essential – growing the same crop repeatedly (e.g. cereals after cereals) quickly leads to disease pressure, declining fertility and weed problems.

Cover crops are also part of crop rotation – the second pillar of conservation agriculture. Crop rotation is discussed in detail in Chapter 4 of e-book 1; here we focus on selecting cover crop species particularly useful in no till agriculture.

How to choose cover crop species in no till farming?

Important! Classic, proven cover crop species include: white mustard, blue phacelia, oil radish, buckwheat, vetch (spring or winter), lupins (yellow, narrow-leaf), forage peas, faba bean, sunflower, winter turnip rape and rye.

In the context of no till farming, it is worth dividing plants into several groups and considering how they behave in mulch (without full incorporation of residues).

Easily degradable and winter-killed plants

These are species that do not tolerate frost and usually winter-kill, and their soft tissue decomposes easily in spring.

Examples: blue phacelia, white mustard, oil radish, buckwheat
-Phacelia is especially recommended as a mulch predecessor for maize or sugar beet, mainly due to its easy decomposition.

Mustard grows quickly and binds a lot of nitrogen, but in mild winters it may partially survive, so it sometimes requires incorporation or mechanical termination.

Oil radish has a strong storage root that breaks compacted soil; after frost it rots, creating channels in the soil (soil drainage). Its thick stems may be worth rolling with a knife roller or mulcher in spring if they remain standing – although they usually soften and lodge.

Buckwheat as a summer cover crop in a reduced tillage system is excellent: it grows even on weaker soils, flowers abundantly (a benefit for bees), dies after the first frost, and also suppresses weeds through allelopathy (it inhibits, among others, dandelion, chamomile-type weeds and amaranth).

High-biomass and winter plants

Examples: rye, winter vetch, winter turnip rape, multi-species winter mixtures
- Rye sown as a cover crop (e.g. in September) will grow in autumn and survive winter, providing cover in early spring. In no till agriculture, rye is sometimes used as living mulch – it can be rolled down in spring (with a knife roller) and the next crop can be direct-drilled. Its advantages are rapid growth, strong soil coverage and allelopathy against weeds. A drawback may be the large amount of residue – rye straw is fibrous and decomposes slowly, which can hinder direct drilling of crops such as maize. When rye is used as a cover crop in a no plough farming, termination (e.g. chemical or mechanical) must be planned early enough.

-Winter vetch and winter turnip rape survive winter and resume growth in spring – they work well as cover until spring (e.g. on erosion-prone slopes or in conservation farming). The vining habit of vetch can make sowing difficult, so it is often sown with a support cereal (e.g. rye or oats).

- Multi-species winter mixtures (e.g. vetch, phacelia, crimson clover, rye, etc.) are gaining popularity because they combine the benefits of many species and cope better with variable conditions. In no till farming, a winter mixture can create a thick cover that must be terminated skilfully, but it leaves a lot of humus.

Small-seeded legume species

They usually grow more slowly and work best as a component of a mixture or as an undersown crop.

Examples: clovers (red, white, Persian), kidney vetch, sainfoin, serradella
- Red clover can produce a lot of biomass and nitrogen, but it has higher water requirements – in a dry summer it may not succeed.
- Lucerne has low frost tolerance, so it may winter-kill, which can be beneficial – it will not regrow the following year.
- Serradella has minimal soil requirements, performs well on sandy soils and tolerates acidity. It is often undersown in winter cereals (rye, triticale) on light soils. It is frost-tolerant, can be sown early and used late into autumn. It does not reduce the yield of the nurse crop, but it thickens the stand and suppresses weeds.

Grasses and cereals as catch crops

Grasses quickly provide cover and a lot of roots, but they strongly draw water from the soil and require nitrogen fertilisation.

Examples: Westerwolds ryegrass (annual), Italian ryegrass, oats, spring barley as cover crops; in no-till systems mixtures are often used, e.g. oats with phacelia and vetch, or ryegrass with clover.

- Ryegrasses are valued in undersowing (e.g. in spring barley) – they emerge, remain after cereal harvest and can be grazed in autumn or cut. However, grasses require fertile soils; otherwise they grow poorly. In no till farming, you should be careful not to sow ryegrass alone and leave it until spring, because it can regrow and become troublesome.

- Oats as a stubble cover crop are sometimes used to produce biomass and remove excess water from the soil (e.g. on wet sites), but they leave a lot of residues. Spring cereals used as cover crops are usually incorporated in late autumn, so their role in no-till is limited (unless used as undersown forage).

Avoiding soil compaction – Controlled Traffic Farming (CTF) and reducing machine pressure

Even the best agronomic practices will not help if heavy agricultural machinery systematically destroys soil structure through compaction. Soil, especially when wet, is susceptible to densification under the wheels of tractors and machines – natural pores collapse, water and air permeability decreases, and roots have restricted growth. In no till agriculture, compacted soil can be harder to fix because deep ploughing is not used to loosen it. That is why minimising compaction is another pillar of long-term soil care.
One modern method is so-called Controlled Traffic Farming (CTF), a system of controlled machine traffic in the field. In CTF, permanent traffic lanes are established – the field is divided into zones: crop lanes (where soil remains soft and is never compacted) and narrow traffic lanes used by all vehicles over many years.

The result? Soil compaction is limited only to narrow lanes, while the rest of the field (most of the area) remains untouched by wheels. It is estimated that in traditional systems even about 60% of the field may be trafficked and compacted during a season, which can reduce yields by 20–30%. With CTF, the total compacted area can drop below 30%.

For farms not ready for full CTF, it is still recommended to follow its core principles: minimise the number of passes, always use existing wheel tracks (do not drive “randomly” across the rest of the field), turn only on headlands, and keep similar wheel track widths and working widths that are multiples of each other – then tools follow the same lanes. With such measures, the trafficked area can be reduced to ~30–40% (instead of >60%).

Beyond CTF, other ways to reduce compaction include combining operations into one pass (as in strip-till where cultivation + sowing happen together). Multifunctional, combined implements significantly reduce total travel distance across the field. For example, instead of cultivating, sowing and rolling separately, you can use an implement that performs these tasks at once. Fewer passes mean not only less compaction, but also fuel and time savings and lower emissions.

Another factor is tyres and pressure: using wide radial tyres, dual wheels or tracks and keeping low tyre pressure in the field (e.g. <1 bar) increases the contact area and reduces unit pressure, so soil is less compressed. It is also important to avoid entering the field with heavy equipment when soil is very wet (e.g. right after heavy rain), because that is when ruts and lasting compaction form most easily.

- Regular soil analysis is also very important. More on this topic can be found in e-books 1 and 2.