Filling an advent calendar with seed bombs

Twenty-four little doors, and behind half of them sits chocolate that nobody wants to see again by January. Seed bombs solve that rather nicely: they take up almost no room, they contain no sugar, and by May there is something on the windowsill that started in December.

Here is how to fill an advent calendar with them without it getting dull by door eight — quantities, wording for the notes, and an honest word about what can and cannot be thrown in December.

1. How many balls does a calendar need?

The simplest version: one ball per door, so twenty-four. That is exactly what the set Twenty-four loose is for — loose balls without packaging, so you can put them in your own paper bags, pouches or boxes.

If the calendar is shared between two children, take two sets or Forty loose straight away. For clubs, schools and groups packing many identical calendars, count with Hundred loose: four calendars per set, plus spares.

2. Not every door needs a ball

A calendar with the same thing behind all twenty-four doors gets tedious. Mixed is better:

• 16 doors

  one seed bomb each, with a short line about what will come out of it.

• 4 doors

  equipment: a bag of soil, a wooden stick as a plant label, a pencil, a small pot.

• 3 doors

  knowledge: a note with a flower, an insect or a question. "Which flower blooms first in the year?"

• 1 door — the 24th

  the big one: the pot filled with soil, ready to go, or a voucher for a shared flower bed in spring.

With that split, sixteen to twenty balls are enough — one set covers a mixed calendar comfortably.

3. Wrapping the individual balls

A seed bomb is about the size of a walnut and weighs about as much. It fits into almost any door — but it crumbles. Bare balls in fabric pouches mean soil in the pouch by 6 December.

• Small paper bags (5 × 7 cm), folded over and stamped. Cheapest and cleanest.
• Greaseproof paper, twisted like a sweet. Looks surprisingly good and costs nothing.
• Glassine or wax paper if the calendar hangs on a line and the parcels are visible.
• No cellophane, no cling film. Sealed tight in a warm flat, residual moisture cannot escape — that is the one reliable way to ruin a ball inside a calendar.

4. So when do they get thrown?

This is the only real catch, and one line on a note solves it: nothing is thrown in December. A ball that lands on frozen grass during advent is bird food. The balls from the calendar get collected, kept dry and sown from March onwards.

If waiting until March is too much: one ball in a pot of seed compost on a bright windowsill, watered in, works in January too. It flowers earlier and smaller, but something happens — and with children that is the whole point. The detail is in the sowing calendar and in seed bombs in winter.

5. Twenty-four lines to copy

6. The timeline

• Early November

  Order the balls. Hand-rolled stock needs drying time, and advent is busy here.

• Mid November

  Get bags, numbers, string and a stamp. Test one ball in one bag before buying twenty-four.

• Late November

  Packing evening. Write the notes, fill the bags, hang it up. Allow two hours.

• 1 December

  Off it goes. Put a jar or box next to the calendar — that is where the opened balls collect.

• March

  Take the jar outside. That is the real second half of the calendar.

7. For clubs, nurseries and companies

Twenty identical calendars at sixteen balls each means 320 pieces. I am happy to plan quantities like that, including a fixed split of mixes so every calendar holds the same. Just send me the number and the date.