For best results, we recommend sowing your seeds soon after receiving them. Each variety is carefully selected to be sown in that specific month, with timing chosen to give your plants enough of a growing window to mature, bloom, or do their thing before the season shifts.

Most seeds will still be viable for a few months if stored in a cool, dry spot (airtight container, dark cupboard, or fridge), but the sooner you sow them, the better your results are likely to be.

You’ll need to supply your own pots or punnets, but we include everything else: growing medium, plant guides, labels, a mini water spritzer and (for our 3 month Spring Wonder boxes only) a heat mat to help things along during the cooler months.

Each seed variety works well in a standard 6-cell punnet, and there’s enough soil in your box to fill one punnet per variety (that’s 12 cells in total per box). 

We haven’t included pots or punnets for a few reasons: it keeps the subscription cost and postage manageable, avoids sending out more plastic than necessary, and let’s be honest, many gardeners already have a few lurking in the shed. If not, garden centres and hardware stores usually stock them cheaply, and some Mitre 10 or Bunnings branches even offer free recycled ones, so it's worth checking locally. Just give any reused containers a quick wash with warm soapy water before planting to help avoid issues with mould or disease.

We’re all for repurposing too, and yoghurt pots can work well in a pinch. Just make sure to poke a few holes in the bottom for drainage. 

As for a propagator lid, you don’t need anything fancy. A clear takeaway lid, cling film, or a lidded plastic punnet from the supermarket (like the ones cherry tomatoes or strawberries come in) will do the job – anything that holds in warmth and humidity while still letting in light. Just lift it occasionally or poke holes for airflow so things don’t get too soggy.
If you prefer something ready-made, you can also pick up reasonably priced windowsill propagator kits from most hardware stores and garden centres.

It’s best to use your heat mat in a bright spot out of all-day direct sunlight – like a bench-top, a shelf near a window, or even the top of the fridge. Germinating seedlings enjoy brightness, so some morning or afternoon sun is fine, but if you pair long hours of harsh sun with bottom heat, things can dry out too quickly.

Think of the heat mat as optional: if your windowsill is already warm and sunny, you may not need it. But it can be really helpful on cooler or darker days, when maintaining a consistently warm temperature makes germination more reliable.

Once seedlings are up and growing, they can move off the heat mat into full sun on a windowsill, and you can remove the lid. You definitely don’t need grow lights for these seeds but if you happen to have some, feel free to use them. Grow lights are much gentler than direct sun when used with a heat mat and can be useful on darker days.

If you’re not using a heat mat, then choose the sunniest windowsill you have (unless the seed’s guide suggests a shadier start). Only Spring Wonder subscribers receive a heat mat in their first box, as it’s helpful for some of the varieties that like extra warmth early on.

If your windowsill still gets really cold or frosty at night, just move the seedlings away until morning – they prefer not to shiver.

Some seeds are quick to appear, others keep you waiting. Most in our collection sprout well before this, but a few can take the full 7–8 weeks depending on the conditions. The expected germination time will be outlined in your seed guide. Seeds often “wait” until things feel closer to their natural environment, so a small tweak – moving them on or off the heat mat, giving them a sunnier spot, or easing them back a little – can sometimes help. Consistent warmth is usually best and your grow guides will note the ideal temperature. Growing from seed is a bit of a patience game, but that makes it all the more exciting when the first green shoots appear. If nothing’s happening by the time the guide suggests you should see action, get in touch and we’ll help troubleshoot.

The mix we include is a fine, free-draining mix designed especially for germinating seeds. It holds moisture without getting soggy and allows air to reach the roots. It’s similar to commercial seed-raising blends and includes peat, bark fines, perlite, and a touch of slow-release fertiliser.

If you need more to sow extra seeds, unless the seed guide specifies something different then look for a standard seed-raising mix. Once your seedlings have grown a few sets of leaves and start to outgrow their cells, it’s time to move them into slightly bigger pots. That’s when a basic potting mix (as long as it drains well) is ideal. Just keep them in a warm, bright spot so they can keep doing their thing.

Some varieties might need something different (like sand, sphagnum/peat moss or succulent mixes). If that’s the case, we’ll always include it to get you started and explain what's needed for transplanting to bigger pots in your growing guide.

Like with any potting mix or growing medium, it’s good practice to avoid breathing in dust (open in a well-ventilated spot), wash your hands afterwards, use gloves if you like, and keep it separate from food prep areas.

Yes, we’ve kept things as recyclable and low-impact as possible. The boxes, tissue paper, shredded paper, seedling labels and seed packets can all go in your recycling bin and the soil pouches and courier envelopes are home-compostable. The stickers are the only exception. The illustrated growing guides are recyclable too, but we hope you’ll want to keep them.

It’s the umbrella for both Stems with Benefits (our food-donating, flower-filled tins) and Stems of Wonder (this side of things, the one with the stranger seeds). Same roots, different shoots – and recently even featured on RNZ.

👉 Explore Stems with Benefits

Feel free to email us anytime at hello@thestemsproject.co.nz. We want you to feel confident and excited about your Stems of Wonder subscription every step of the way!