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Zucchini, cucumber, and pumpkin seeds

Zucchinis, cucumbers, and pumpkins are really fun to grow.
Pompoenen, courgettes en komkommers zijn super leuk om zelf te kweken
Zucchinis and pumpkins: fun to harvest
They take up a lot of space, but if you choose the right varieties, you can grow them on a trellis. Those kinds are perfect for a Planty Garden.

But as soon as you mention growing zucchini and pumpkins, there's always someone who says:

"Yes, but wait a minute: home-grown zucchini - or pumpkins - can be deadly poisonous. It's best not to sow those yourself."

Okay, let's dig into that a little deeper.

Are homegrown zucchini and pumpkin poisonous?

No. Only in really exceptional cases.

Still, the story of the poisonous zucchini pops up every year. There's also a variant that produces poisonous pumpkins. That usually rings a bell, but most people don't know much more about it.
Giftige courgettes en pompoen: waar komt dat verhaal vandaan?
Ripe pumpkin, ready to harvest
Here's the thing:

As far as I know, only 1 person has died from a poisonous zucchini.

That was a German man who passed away after eating a zucchini from his own vegetable garden. That zucchini contained extremely high levels of cucurbitacin: a poison that occurs naturally in all cucurbits (Cucurbitaceae).

If you grow zucchini from newly purchased seeds, the fruits they bear won't be poisonous. The poison has long since been bred out of the seeds.

When can cucurbitacins reappear?

You have to do a lot for that to happen:
  1. You have to sow zucchinis year after year from seeds collected from your own garden.
  2. You have to grow inedible ornamental gourds alongside edible zucchinis and pumpkins.
  3. You have to harvest seeds from zucchinis or pumpkins that have been fertilized with pollen from the ornamental gourd.
  4. You have to have all those things happen for several years.
Only then can the cucurbitacin levels rise. And even then, it rarely happens.

Still, that's what happened to the man in Germany. He kept on growing from his own seeds year after year.

How do you know if the fruit is poisonous or not?

You can taste the poison immediately: the zucchini or pumpkin is extremely bitter. It's totally inedible. Believe me: you'll spit it out right away.

But let's say for some reason, you don't taste the difference. Then you still have to eat a lot of it before you'll get sick, let alone have it kill you. You'd have to be in pretty bad health to start with too.

How can I be 100% sure this won't happen to me?

Simple. Use new seeds. Preferably ours of course 😀
Giftige courgette - klimmende courgette Makkelijke Moestuin
Our climbing zucchini
Seed growers only harvest seeds from plants that are separated from other vegetables.

This isn't just the case for zucchini and pumpkin, but with all plants. It makes sense: otherwise, they can't guarantee what exactly the seeds will produce.

If you want to harvest your own seeds from your plants, just make sure there are no ornamental gourds anywhere nearby.

But what about cucumbers?

Homegrown cucumbers can sometimes taste a little bitter. Actually, it's the same substance, but there's just not much of it.

Cucurbitacins reappear when the fruits don't get enough water. Usually, just the tip of the cucumber will taste a little bitter, not in the whole cucumber.

This is especially prevalent in old varieties, like heritage seeds.
Komkommer Iznik kan niet bitter worden
Cucumber Iznik: can't get bitter
Our cucumbers and zucchinis are special varieties. They're bred so they won't become bitter, even in extreme heat or drought.

That's an extra safe bet 😄
Good luck with sowing!

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