Can You Plant a Field by Throwing Things at It? Sometimes, and Rarely Well
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Seeds wrapped in clay and compost can be thrown onto ground that cannot be dug or reached. The idea is old, the enthusiasm is recent and the results are mixed.
What the object is
The construction is a ball of clay and compost containing seeds, dried until firm. The clay protects the seeds from birds, ants and rodents and holds them in place rather than letting them blow away, and it does not break down until it has absorbed enough rain to soften, which delays germination until there is moisture in the ground. The compost supplies the seedling with something to grow in when it does germinate, which matters on compacted or poor ground. Thrown onto a surface, the ball sits there through dry weather and dissolves when it rains, releasing the seeds into a small patch of prepared material.
Where it makes sense
The technique suits ground that ordinary sowing cannot reach:
- •Steep slopes and eroding banks where nobody can stand
- •Land after fire, where speed matters and access is poor
- •Ground too compacted or stony to be cultivated
- •Areas being seeded from the air, where loose seed would blow away
- •Sites where soil disturbance would release stored carbon or seeds of weeds
- •Places nobody is permitted to enter to plant
Why it frequently fails
Enthusiasm for the technique routinely outruns the results, and the reasons are consistent. Seed needs contact with soil and moisture to establish, and a ball sitting on hard ground or thick grass supplies neither. Established vegetation outcompetes a seedling with no advantage, so throwing seed into a meadow that is already full achieves almost nothing. The species chosen are frequently unsuitable for the site or are not native to it, and commercial mixes have introduced inappropriate and occasionally invasive plants. And throwing seed onto land somebody else owns or manages is unlawful and can wreck a deliberate management plan that the thrower knew nothing about.
How to make one that works
Where the technique is appropriate, the construction details determine whether anything grows. The usual mixture is roughly five parts clay to one part compost with a small quantity of seed, mixed damp and rolled to about the size of a walnut, then dried slowly out of direct sun so the ball firms without cracking. Too much clay makes a ball that never breaks down, and too little leaves it crumbling in the hand. Seed should be native, locally sourced and suited to the site, and mixing many species is generally better than one, since which one establishes depends on conditions nobody can predict. Sowing in autumn suits species that need winter cold.
The history behind it
The practice has two quite separate ancestries that are frequently merged. Clay-coated seed is an old agricultural technique, revived and promoted in the twentieth century by the Japanese farmer Masanobu Fukuoka as part of a no-tillage system in which the coating protected seed broadcast onto uncultivated ground, and his approach was a whole method of farming rather than a gesture. The modern thrown version comes from guerrilla gardening in New York in the 1970s, where a group began throwing seed-filled containers over fences into derelict lots as a form of direct action, which is a political practice with horticulture attached rather than the reverse.
The takeaway
Clay and compost around seed protect it from animals, hold it in place and delay germination until rain softens the ball, which suits steep, burnt, compacted or inaccessible ground. It fails where the ball sits on hard surfaces or in established vegetation that outcompetes any seedling, and commercial mixes have spread unsuitable species. The agricultural version and the guerrilla gardening version have separate origins.