There are no guarantees when you farm under God’s sky. You don’t know for certain when you can plant, when rain will fall, whether the year will be hot or cool, or when and how much soil nitrogen will be released from the soil. And any or all of these can affect yield and quality of all crops, especially grains used for processing, such as malting barley and milling wheat.

That said, there is no magic formula for achieving the quality specs to meet the market requirements. The past five years showed this clearly in the case of malting barley. This year, the market is changing to reflect consumption preference and producers are being asked to move in the same direction and to produce malting barley across a wider band of protein specs.

But the field is not a factory and there are many factors that affect grain quality which are beyond our control. We must still do all we can to try and tighten up our delivered spec. But we can never guarantee to produce the spec that is required for computer-controlled malting, brewing and distilling processes.

In some respects, the opening up of both markets is useful as it widens the spec on the lower side of protein requirement. However, achieving a wider band of protein may not be simple and must be planned for. This year’s Tillage Conference presentations showed the challenges of meeting the combined yield and protein targets as the combination of applied nitrogen and soil nitrogen availability are critical in combining optimum yield with the required protein.

While the difficulties are real, we must focus on what we can do to help achieve these targets and a step-by-step approach is useful. In this article, I look at matters relating to the starting point of crops – soil fertility, soil management, seed beds, seeding rates, plant counts and seedbed nitrogen – and next week I will look at the general management of the crop.

Get the basics right

Start with the basics. This may seem like old hat, but the basics remain vital for spring barley production. Variety is important but individual growers have no choice in this given the production structure that is in place to ensure product purity. After that, the challenge is to have soil fertility and soil physical condition in top shape so that the growing crops remain in top gear post establishment.

Field choice is important for the different target specs. Lower proteins will be easier to achieve on lighter more worn ground, while stronger ground and heavier land will tend to have higher protein. Nitrogen rate and timing will be important here too, but more about that later.

Soils and fertility

Soil fertility should be under control before you plant. Traditionally, soil fertility was maintained through the presence of sugar beet in rotations. When this ceased, too many growers took their eye off the ball and a lot of corrective action had to be taken in recent years on both pH, phosphorous and potassium levels.

Growers know that it is preferable that spring barley suffer no setback between establishment and ripening. So, everything needs to be right. Good soil fertility is important to help achieve this, as is a good seedbed. It is preferable that soil fertility is at Index 3 for all crops rather than having to put on more to achieve less.

Soil pH or lime status is most important. Having soil pH correct (6.8) increases the availability of the phosphorus (P) and potassium (K) that is in the soil and also of the applied product. Low pH decreases nutrient availability and use efficiency and, therefore, yield potential. The use of fast-acting granular lime should be considered in the crop where pH is below optimum.

Good soil tests, appropriately taken to reflect either field or yield variability and possible fertility, are a critical starting point.

There are more and more examples of significant fertility variability within uniformly treated fields (possibly resulting from soil variability) and these need to be tackled to help provide the desired uniform quality. Taking more rather than fewer soil samples is important to guide fertilizer application. This is equally important for pH, P, K and minor elements.

Crops get their nutrients from a combination of applied nutrients and soil available nutrients. A growing crop requires much more than is applied and it needs to get this from the soil. At the end of the growing season, much of this is then returned to the soil during the ripening process and is available again for the next crop. This is shown graphically in figure 1.

Increased soil availability adds to the potential to take up more to help increase yield potential. Increased yield will result in lower protein where the same amount of nitrogen (N) is used.

You should aim to get your soils up to Index 3 but this is difficult on rented ground. A 7.5t/ha crop of spring barley will remove 29kg P/ha, plus 86kg K/ha, where straw is removed and these must be replaced to avoid fertility depletion. Total offtake is influenced by yield and P should be adjusted by 3.8kg P/ha per tonne (above or below 6.5t/ha) and K by 11.4kg/ha per tonne of grain yield.

The recommended application rates for P and K to produce a 7.5 t/ha crop are shown in table 1.

Another important aspect of soil is its physical condition. Tight worn soils are not the best environment for fast-growing roots to produce top yields. Soils that receive regular organic manuring with any one of a range of products will be inherently healthier. Open, well-structured soils drain more easily and breathe more easily to facilitate maximum growth.

As well as being more open, healthy soils are always being repaired as earthworms and other soil organisms act to produce humus in the soil. Humus is a mixture of organic matter, in various stages of breakdown, plus fine damaged soil particles and these are bound together by a range of soil fungi.

Humus is useful as a moisture store on lighter land in a dry season and is much better than soil alone. Humus is also a useful store for plant nutrients which are held on its surface and therefore much more available to plant roots than nutrients bound by clay particles. So, the trick is to provide the conditions to generate humus to drive crop yield in the long term.

Fertility issues should be sorted out in advance of planting. Where soil tests indicate Index 1 or 2, the fertilizer should be combine-drilled with the seed for quick access to drive early season growth. This is less critical at Index 3 and not an issue at Index 4. Even on these soils it is always preferable to put the fertilizer into the seedbed where it can dissolve and be available to the crop. Applying critical fertilizer on top post-emergence could result in slowed availability if a dry spell followed application.

Seed bed

Spring crops need to get up and running fast and then stay growing to the end. Good seedbeds are critical in this regard. Fine, firm and level seedbeds are the basic starting point for all crops. Fine, firm and level help the uniformity of planting, germination and establishment. Fine and firm help moisture transfer to the seed for germination and, more importantly, they help root soil contact for nutrient uptake and growth. These are even more important with later planting, as the season is shortened.

Good consolidation is the making of any seedbed. Remember, a roller only firms the surface and the soil beneath where the roots are trying to forage can often be quite loose. So, think more about deep consolidation as the roller mainly does surface-levelling and firming.

Roll post-sowing, if possible, and if you have a ridged seedbed (bad ploughing) consider rolling it at right angles to the drill, so that the roller can sit into the hollows rather than just riding on the ridges. Get the ploughman to roll it if he was responsible for the bad ploughing.

Seeding rate

The seed rate is important for spring barley. We all know that plants will tiller if the population is low but low plant populations will end up producing secondary and even tertiary tillers to fill the spaces. So, the crop may look okay but these later formed grains can have different physiological characteristics which can come through in brewing, and especially in distilling, to alter the product characteristics. The best crop structure is produced from uniform establishment of a moderately high seed population.

For this reason, there are target plant populations set for these barley crops of around 300 to 320 plants per square metre. But establishment is never 100% and, so, you need to plant more seeds to leave the target plant population.

In good conditions, 85% establishment is about normal and this means 350 to 370 seeds per square metre. On 50g TGW seed, this would require 175kg to 185kg/ha (11.1 to 11.8 st/ac) of seed. Indeed, for crops likely to have lower protein for the distilling market, it is suggested that the plant population should be closer to 350/m2 and this would push the seed rate for the previous seed spec up to 205kg/ha (13 st/ac).

To work out your own seed rate, you can use the formula in the shaded box below.

Alternatively, you can use the figures in table 2 to get the seed rates to produce plant populations at different seed thousand grain weights (TGW). But these need to be adjusted by the likely establishment level to achieve the desired plant population.

Table 3 provides basic information to help estimate the likely percentage establishment. For later sowing, it is useful to consider higher seed rates as there is less time for natural tillering. In this case, it is even more important to have the fertilizer in the seedbed. If you do not have a combine drill, try and get the ground rolled before applying the fertilizer and incorporate it during drilling. You could consider slightly more N in the seedbed as the season gets later. Use the most appropriate compound fertilizer to supply the level of nutrients required for your field.

Nitrogen

This is key to achieving the required combination of yield and quality. Part of the total N requirement is applied by the grower and the remainder is supplied by the soil. It is this soil component that makes management difficult. Nature alone governs how these inputs behave, and both can have a major impact on yield and quality.

In this article, I only make reference to seedbed nitrogen and will give further information on top dressing next week. For fields destined for distilling, apply more of the total (up to 60kg N/ha) in the seedbed so as to have less on later to help keep down grain protein levels. For fields destined for brewing, consider about 30kg to 45kg N/ha in the seedbed with one or two subsequent splits depending on your land.

Grains per unit area is the most important yield component in barley and ear count at, or slightly above, 1000/m2 is the most reliable way to achieve the optimum. If you start at 300 plants and you produce 2.5 viable tillers per plant (plus the main stem) you produce just over 1,000 ears/m2. Having counts to establish the plant population can help with the husbandry. If you have a low plant count, you might consider more of your N early.

There are many ways to count plants but it is generally agreed that counting a linear length is better and easier than counting a specific area. The only difference is that the linear count must be converted into area based on the row width. Many drills differ in establishment between the front and rear drill counters. For this reason, it is best to take the count from two neighbouring rows to give the count per two metres and then convert this into a square metre using the guidelines in table 4.

Tillering is best left to nature, if possible. Interfering with natural tillering can force the production of far more tillers and even more of these can subsequently die. The breaking of apical dominance may be more inclined to leave you with more secondary and tertiary tillers, the grains from which are known to be problematic for distilling in particular. A primary tiller is produced from a leaf on the main stem; a secondary tiller is produced from a leaf on a primary tiller; a tertiary tiller is produced from a leaf on a secondary tiller.

Stages

It is important to understand the different stages of growth of the plant because when you apply an input it will interfere with what the plant is doing at that time. If you want nitrogen to help produce more tillers, you must apply it during early tillering. Seedbed N will have the same effect and it is ‘dryness proofed’.

The growth stages are simple and they are described in sets of 10 (decades). The ‘10s’ describe the number of leaves – GS12 has two unfolded leaves on the main stem. By the time you have five leaves, an older one may have died or there may be a big number of tillers present and so counting leaves is almost impossible. So, we move on to counting tillers – the ‘20s’. GS22 has two tillers. Then we move on to stem extension. GS31 is first node present; GS33 is three nodes; GS37 is flag leaf just visible and GS39 is flag leaf fully emerged. It all happens in logical format. Knowing the growth stages helps you get more from your other inputs.

Even for a similar planting date, specific growth stages can often occur at different times. Take last year, for example. Spring growth and growth stage development was very slow. Who knows what this year will bring but it is possible that later planting could make growth stages appear faster, especially if we get high spring temperatures. Manage your crop according to its growth stages, not calendar date.