Question 1

What is a grass budget?

Accepted Answer

A grass budget is a month-by-month forecast of grass supply versus livestock demand on your farm. It tells you which months you will have surplus grass (available to close for silage) and which months you will have a deficit (requiring conserved feed or concentrate to bridge the gap). Running a grass budget at the start of the season allows you to plan silage cuts, adjust stocking rate, or arrange bought-in feed before shortfalls occur.

Question 2

What are typical UK grass growth rates?

Accepted Answer

UK lowland grass growth rates vary enormously through the year. In January and February growth is minimal — typically 10–20 kg DM/ha/day. Spring flush in April and May sees the fastest growth of the year — 70–100 kg DM/ha/day on good lowland farms. Summer growth slows in July and August (65–80 kg DM/ha/day) before a secondary autumn flush in September (40–50 kg DM/ha/day). By November and December growth drops back to 15–20 kg DM/ha/day. Upland and hill farms see significantly lower growth rates throughout, particularly in winter.

Question 3

What does the surplus figure mean?

Accepted Answer

Monthly surplus (shown as positive on the chart) is the difference between how much grass your land produces that month and how much your herd eats. A large surplus in May and June means paddocks are growing faster than the herd can graze them — this grass should be closed and cut for silage. A deficit (negative figure) means the herd needs more feed than the farm produces that month — bridged by silage fed from stores, bought-in forage, or concentrate.

Question 4

How does this differ from the grass wedge planner?

Accepted Answer

The Grass Wedge Planner uses your actual paddock cover readings to show where you are today relative to your targets. It is a real-time operational tool. The Grass Budget Planner uses assumed growth curves to forecast how supply and demand will balance across the whole year — it is a planning tool for the season ahead. Use the grass budget to plan silage and identify likely deficit periods, then use the grass wedge to manage the rotation week by week.

Question 5

Why does the calculator show a large surplus in May and June?

Accepted Answer

Spring growth rates on UK lowland farms typically reach 80–100 kg DM/ha/day in May — far faster than a housed or recently turned-out herd can consume. This surplus is normal and expected. The standard response is to close paddocks for 1st cut silage in late April or May, which removes the surplus and builds your winter feed store. The Grass Budget calculator identifies this surplus explicitly so you can plan silage cuts and contractor bookings in advance.

Grass Budget Planner

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