This clay soil improvement planner helps gardeners stuck with heavy clay beds turn a soil guess into a clear plan. You enter a few numbers, and the tool works out the amounts for you. That matters because soil is the one garden input you cannot fix in a day: too little organic matter and plants starve, too much of one amendment and the mix goes wrong for a whole season. A written plan keeps each bed balanced, so plants grow without stress.
Clay soil is rich in nutrients, but it holds water too well. When wet it sticks to boots and tools, and when dry it cracks into hard bricks. The fix is not a single digging session: it is a season of organic matter, added on top, that worms and roots pull down into the clay. Compost opens the structure, mulch stops the surface baking, and cover-crop roots break channels deep into the bed. Given one full season, even heavy clay turns crumbly and workable.
To use the tool, enter each value in order: Bed area in square metres, Compost depth in cm, Months in the plan. Then press Calculate to see the result. Each line shows one part of the plan, so you can spot a number that looks wrong before you carry a bag outside. If you change any value, press Calculate again. The example button fills in a worked case so you can see how the tool behaves before you enter your own numbers.
Here is a worked example. Take a 10 square metre clay bed with 5 cm of compost over a 6 month plan needs 500 litres of compost, which is 13 bags of 40 litres, plus 500 litres of mulch, with 6 monthly top-up sessions. That result is the point of the tool: one clear plan, with each part visible. If a neighbour asks why you mixed the soil that way, you can walk through the same lines. If your bed is bigger or smaller, you change one number and the plan updates. That makes changes fast and keeps the garden honest about what each bed really needs.
Start in autumn, when clay is damp but not soaked: spread compost thickly and sow a cover crop such as crimson clover on bare beds. Let winter frost break the clods for you, and do not dig until the soil crumbles in your hand. In spring, plant into the improved top layer and mulch at once. By summer, the bed should drain after rain instead of puddling, and that is the sign the plan is working.
Three mistakes show up again and again. The first is digging wet clay, which destroys its structure and makes compaction worse. The second is adding sand, which can set the clay like concrete. The third is expecting one weekend of work to fix years of compaction: clay improves over seasons, not days. Be patient, keep adding organic matter, and stay off wet beds.
Tips
- Test a small patch first. One pot or one corner tells you more than a whole bed mixed on a guess.
- Add organic matter every season. Soil life eats compost, so a bed fed once slowly goes hungry again.
- Mulch every bed. Bare soil dries fast, while mulched soil holds water for days longer.
How do I know if my soil improved?
Squeeze a handful of damp soil: good soil crumbles softly instead of sticking in a lump or falling to dust. Also watch drainage after rain and how long beds stay moist in a dry week.
Can I mix too much of an amendment?
Yes. Most amendments help in a modest share and hurt in excess, so follow the tool result and mix evenly rather than tipping in a whole bag at once.
How often should I re-test or re-plan?
Once a season is enough for most beds. Re-plan after a wet winter, after adding a large amount of compost, or when a bed starts behaving differently from its neighbours.
Versión en español: Planificador para Mejorar Suelo Arcilloso