From Tiny Seeds to Curious Tingling Flowers

A friendly guide to sowing, growing and enjoying Toothache Plant in Hungary.

Come Into the Garden With Me…

Today, we're growing one of the strangest little flowers in the seed box: Toothache Plant.

At first glance it looks playful rather than dramatic, with compact green growth and little rounded yellow flower heads with darker red centres. But this is a plant people remember for another reason: the flowers can create a spicy, tingling, mouth-numbing sensation when tasted.

Our Holland Kertészet packet is  Toothache Plant, labelled Spilanthes oleracea. You may also see the plant called Acmella oleracea in gardening references.

For us in Hungary, this is very much a warm-season annual. It dislikes frost, wants warm soil and performs best once spring has properly settled. Its compact size also makes it wonderfully easy to grow in pots, raised beds and the front of a sunny border.

We will start with those tiny seeds, learn how warm they like to be, how to keep seedlings sturdy, when to plant outside, how to water through a Hungarian summer, what those famous tingling flowers are like, and how to save seed for another year.

Ready? Let's grow something that will definitely start a conversation.

1. Meet the Toothache Plant

Toothache Plant belongs to the daisy family, Asteraceae. It is widely known under several botanical names, including Spilanthes oleracea and Acmella oleracea, so do not be surprised if you see both names in seed catalogues or gardening books.

What does it look like?

The plant forms a low, leafy mound with branching stems and rounded to oval green leaves. The flowers are unlike ordinary daisies: small, rounded yellow buttons with a darker red centre, often compared with tiny eyeballs or miniature pom-poms.

How big does it get?

The Horti Tops packet lists a mature height of around 30 cm. That compact size makes it especially useful where taller summer flowers would be awkward, including the front of borders, raised beds and containers.

Annual in Hungary

In warm climates Acmella can behave as a tender perennial, but in Hungary it is best treated as an annual. Frost will finish the plant, so we grow it from spring through autumn and begin again from seed the following year.

2. Give It Warmth, Light and Steady Moisture

Toothache Plant is happiest when three things come together: warmth, good light and soil that stays reasonably moist without becoming waterlogged.

Warmth matters

Do not rush it outdoors. Hungarian nights can remain surprisingly cool in April even after several sunny days. Wait until frost danger has passed and the soil has warmed before planting permanently outside.

Sun is best

Give the plant a bright position. Full sun encourages the strongest flowering, although a little light shade is usually tolerated, especially during the hottest part of the day.

Moist but well drained

Use fertile but well-drained soil. Toothache Plant likes more moisture than drought-loving Mediterranean herbs, but roots should never sit in stagnant water.

In containers, a free-draining potting mix is ideal. In heavy Hungarian clay, improve structure and avoid low places where water collects after storms.

3. The Toothache Plant We Grow With You

At a glance

The packet is labelled Spilanthes oleracea. It is grown as an annual in Hungary, reaches about 30 cm and produces yellow flower heads with a red centre.

Protected sowing is listed from February to May, while outdoor sowing begins from May once warm weather has arrived. The packet advises pricking out seedlings when they are about 2 cm tall.

Why this plant is different

Many flowers are grown only to look at. Toothache Plant is memorable because sight, taste and sensation are all part of the experience. The flowers are edible and have a spicy, peppery, tingling effect.

A compact plant with many uses

Its size makes it especially useful in pots, at the front of a border or near a terrace or kitchen door where people can inspect the unusual flowers closely.

4. Let’s Sow the Seeds

Toothache Plant seed is small and germinates best with warmth and light. For beginners, starting under glass or indoors is usually the easiest route.

When to sow

The Horti Tops packet allows protected sowing from February to May. For most home growers in Hungary, March or April is a practical sweet spot: early enough for a long season, but late enough to provide stronger natural light.

How to sow

Fill a tray or small pots with fine seed compost and water before sowing. Scatter the seed thinly over the surface, press it gently into contact with the compost and cover only extremely lightly, if at all.

Keep the seed warm - roughly 20-25°C - and evenly moist. As soon as seedlings appear, give them good light so they remain compact rather than pale and stretched.

Pricking out

The packet tells you to prick out seedlings when they are about 2 cm tall. Handle them by a leaf rather than squeezing the delicate stem, and move them into small individual pots or a wider tray.

5. Planting Out in Hungary

Once the seedlings are growing strongly and the weather has warmed, begin hardening them off. Put them outside for gradually longer periods over about a week, then plant permanently after the risk of frost has passed.

Spacing

Around 25-30 cm between plants gives enough room for branching without creating a crowded mass. In a pot, one plant in a medium container can make a neat specimen; several can share a larger trough.

Water after planting

Water thoroughly after transplanting and keep the soil gently moist during the first weeks. Once roots are established, the plant becomes more forgiving, but prolonged drought will reduce growth and flowering.

Pots are an excellent choice

Because the plant stays compact, a container on a sunny terrace is ideal. A pot also lets you control moisture more easily and move the plant if an unexpectedly cold night threatens.

6. Summer Care: Keep It Growing and Flowering

Once warm weather settles in, Toothache Plant grows quickly and needs only straightforward summer care.

Watering

Aim for steady moisture rather than alternating between bone-dry soil and flooding. In hot Hungarian weather, morning watering is usually best.

Container plants can dry remarkably fast in July and August. Check the compost regularly and water before the plant wilts badly.

Feeding

In ordinary garden soil, heavy feeding is unnecessary. Container plants can receive a light liquid feed every few weeks once active growth is underway.

Deadheading

Remove older flower heads if you want the plant to keep making new ones. If you want seed, leave several healthy late-season heads to mature fully.

Pinching

Young plants can be pinched lightly to encourage extra branching. More branches usually mean more flower heads later in the season.

7. The Famous Tingling Flowers - and Safety

The flowers contain compounds including spilanthol, which creates the characteristic tingling and numbing sensation. The effect can be surprisingly strong, especially if you taste a whole fresh flower head rather than a tiny piece.

How to approach it

If you choose to taste the edible flowers, begin with a very small piece. The sensation can include tingling, increased saliva, a peppery feeling and temporary numbness.

Kitchen use

The flowers are sometimes used as a novelty garnish or in small amounts where the tingling sensation is part of the experience. The leaves can also be used, though the distinctive effect is strongest in the flower heads.

The important limit

Do not use Toothache Plant to delay diagnosis or treatment of tooth pain. Persistent toothache needs professional dental assessment because pain can signal decay, infection or another problem that the plant cannot fix.

8. When Something Goes Wrong

Toothache Plant is generally uncomplicated once warm weather arrives, but a few problems are worth recognising early.

Seedlings are not appearing

Check temperature first. Cold compost slows germination. Keep the seed warm, near the surface and evenly moist.

Plants are pale and slow

Cold weather, poor soil or waterlogged roots are common causes. Wait for warmth, improve drainage and feed lightly if the plant is in an exhausted container mix.

Plants wilt every afternoon

In a pot, this usually means the root ball is drying too fast. Water deeply and, if necessary, move the container out of the fiercest afternoon heat.

Slugs and snails

Tender young plants can be attractive to slugs and snails. Protect seedlings especially during damp spring weather.

Very leafy, few flowers

Too much nitrogen and too little sun can push the plant toward soft leafy growth. Reduce feeding and increase light where possible.

9. Saving Seed and the End of the Season

If you want to grow Toothache Plant again next year, allow several healthy late-season flower heads to remain on the plant and mature fully.

Collecting seed

Once the heads are completely dry, collect them on a dry day and rub them gently to release the seed. Finish drying the seed indoors if necessary before storage.

Choose strong plants

Collect from healthy, vigorous plants that flowered well. That gives you sensible starting material for next season.

Store it dry

Keep cleaned seed in a labelled paper envelope somewhere cool, dark and dry. Write the plant name and year on the packet so there is no mystery next spring.

Then frost arrives

Toothache Plant does not survive Hungarian winter outdoors. Once autumn frost finishes the plants, remove healthy material to the compost and keep your saved seed dry until the next warm season.

The rhythm of the year

February is the earliest protected sowing point if you have reliable warmth and strong light, but March is often an easier month for home growers. April is ideal for continuing indoor sowing and pricking out young seedlings.

May is the turning point. Once frost risk has passed, harden plants off, begin outdoor sowing and let the warmer soil take over. June brings rapid establishment, while July and August are the months when steady watering matters most, especially in pots.

By September, you can still enjoy late flowers while deliberately leaving a few good heads for seed. October is the month to collect those dry heads before hard frost and persistent autumn rain finish the season.

10. Your Toothache Plant Cheat Sheet

We've gone from almost dust-fine seed to one of the strangest flowers in the summer garden. Here's the whole journey in one place.

1. Toothache Plant is sold as Spilanthes oleracea and is also known as Acmella oleracea.

2. Grow it as an annual in Hungary.

4. Expect plants around 30 cm tall.

5. The flowers are yellow with a darker red centre.

6. Protected sowing is possible from February to May.

7. March or April is a practical indoor sowing period for many Hungarian gardeners.

8. Outdoor sowing begins from May once warmth has arrived.

9. Surface sow or cover the seed only extremely lightly.

10. Keep germination warm, around 20-25°C.

11. Give seedlings bright light after emergence.

12. Prick out seedlings at about 2 cm tall.

13. Harden plants off before permanent outdoor planting.

14. Space plants roughly 25-30 cm apart.

15. Choose full sun to light shade.

16. Keep the soil fertile, moist and well drained.

17. Water containers carefully during hot July and August weather.

18. The flowers have a spicy, tingling, numbing effect.

19. Treat the flowers as a culinary curiosity, not dental treatment.

20. Save fully dry late-season flower heads if you want seed for next year.

If You Remember Only Five Things…

1. Warmth matters

This is a warm-season plant. Do not rush it outdoors while Hungarian nights are still cold.

2. Keep the seed near the surface

The tiny seed benefits from light. Press it onto moist compost and cover only extremely lightly, if at all.

3. Give it steady moisture

Warmth does not mean drought. Keep young plants and containers evenly moist without waterlogging the roots.

4. Start tiny if you taste it

The famous tingling sensation can be surprisingly strong. A very small piece is enough to discover what the plant does.

5. It is not dental treatment

Enjoy the name and the curiosity, but persistent tooth pain belongs with a dentist, not a flower head.

One Last Walk Around the Garden

Do you remember where we started?

With a 0.08 g packet of tiny seed and a plant with one of the strangest names in the garden.

We kept the seed warm and close to the surface. We watched for those first tiny seedlings, pricked them out carefully, waited for frost danger to pass, and only then introduced them to the Hungarian summer.

The plants never became enormous. They did not need to. A compact mound of green leaves was enough to carry those curious yellow-and-red button flowers exactly where we could see them.

Then came the moment this plant is famous for: the first cautious taste. A little peppery warmth, tingling, extra saliva, then that unmistakable temporary numbness that explains why generations of gardeners remembered the common name.

But by the end of the season, you know the plant for more than that one trick. You know how quickly its pot dries in July. You know how much sun it likes. You know whether pinching gives you the shape you prefer. And you know how many flower heads to leave if you want seed for next year.

That is what this series is really about: not memorising instructions, but learning a plant until it begins to feel familiar.

So enjoy the last curious flowers. Save a few dry heads for seed. And when frost finally ends the season, put that little labelled packet somewhere safe for spring.

And when you're ready for the next plant…

Come into the garden with me.