Techniques Sowing and starting indoors

Starting courgettes, pumpkins and cucumbers indoors

The best time to start courgettes and pumpkins indoors is from late April to late May. Our fast-growing Snack cucumber can even be started in July.
Espenada Snack cucumber growing on the plant
Espenada Snack cucumber
Many gardeners do it earlier, but you don't need to: the plants grow super fast.

Plus, caring for your plants on the windowsill isn't so easy. They often don't get enough light. So, the less time you spend growing them indoors, the better. (You can even start as late as mid-June).

How do you start courgettes, cucumbers and pumpkins indoors?

It is very simple. Follow the app if you use it; otherwise, here is an overview:

1. Start by pre-sprouting the seeds

Why? Because it lets you check that the seeds have germinated properly. Our cucumber and climbing courgette seeds are expensive, so it would be a shame to leave it to chance.

It is easy: dampen a piece of kitchen paper or toilet paper and place the seeds between the layers.
Vegetable seeds pre-sprouting between damp kitchen paper
Pre-sprouting seeds between damp kitchen paper
To keep the kitchen paper from drying out, I use shallow dishes covered with cling film.

Take care not to make the paper too wet, as the seeds may become mouldy.

Place the dishes somewhere warm. The seeds germinate at about 21°C; if it is colder, they will not do anything. Check occasionally for a root. You may see one after 2 to 3 days, although it sometimes takes longer.
Snack cucumber seeds with newly emerged roots
Snack cucumber seeds have roots after 2 days

2. Put the germinated seeds into an Airpot

You will need:
Please note: MM coconut seed-starting mix does not contain nutrients when it comes out of the bag. When preparing a new bag, add one heaped tablespoon of MM plant food.

Seed-starting mix contains fewer nutrients than ordinary mix, which is exactly what seedlings need. Too many nutrients make them grow too quickly, leaving them weak rather than sturdy.

Fill the Airpots with seed-starting mix and moisten it. Make a fairly wide hole around 1 cm deep in the centre of each pot. Carefully place one germinated seed in each hole without damaging the root.
Germinated courgette seed planted in an Airpot
A germinated courgette seed in an Airpot with coconut seed-starting mix
If you do not have Airpots, ordinary pots work too. Choose fairly large ones, at least 15 cm in diameter.

Place the pots in a bowl or saucer and put them somewhere warm, such as a windowsill.

That's it.
Pots of newly sown summer vegetables on a windowsill
Newly sown summer vegetables on the windowsill

Seedlings on the windowsill

When you start seeds this way, the seedlings soon emerge from the mix. As soon as they do, remove the cling film (not needed with coconut mix) and place the pots in plenty of light. Do not let them become too warm: 20°C is the maximum.
Young pumpkin seedling just emerging from seed-starting mix
A newly emerged pumpkin seedling
Check regularly that the mix is still damp, as small seedlings dry out quickly. Water pots with traditional seed-starting mix from above; for coconut seed-starting mix, add water to the dish beneath the pot.

Turn the pots a quarter turn every day to prevent the seedlings from leaning to one side.

One week later, they already look like this:
Young courgette, cucumber and pumpkin seedlings
Courgette, cucumber and pumpkin seedlings

Rapid growth

Pumpkins, cucumbers and courgettes grow extremely quickly. If you start them in late April or early May, the plants can go outside fairly soon.

Before planting them outside permanently, gradually get them used to outdoor conditions by leaving them out for one hour longer each day.
Young summer vegetables being hardened off outdoors
Getting used to outdoor conditions with tomatoes and other plants
Once they are used to outdoor conditions, plant them outside around the end of May. By then, they will probably be sturdy young plants.

Plant them in a square beside a strong trellis:
Young courgette planted beside a trellis
A young courgette plant beside the trellis

Climbing courgette

A sturdy trellis is especially important for the climbing courgette. The mature plant produces plenty of courgettes, and together they become quite heavy:
Mature climbing courgette trained up a sturdy trellis
A mature climbing courgette beside the trellis
For detailed instructions on caring for this plant in your raised bed, see Climbing courgette in the shop. The product page includes a full description and photographs:

Snack cucumber

Our Snack cucumber grows so quickly that you can even sow it in July.

We sowed this plant at the end of July and harvested the first small cucumbers by mid-September. It soon produced plenty more. This photograph was taken in mid-October:
Snack cucumber sown in late July and producing fruit in mid-October
Snack cucumber on 14 October, sown in late July
Read how to achieve this on the Snack cucumber page in the shop. It describes every growing stage and includes photographs.

Baby pumpkin

Still have a little room beside your cucumbers and tall tomatoes? Try a Baby pumpkin. Its fruits are fairly small, so you can train the plant up a trellis too.
Small Baby pumpkin fruit hanging from a trellis
Baby pumpkin growing on a trellis
Our pumpkins grow a little differently from climbing courgettes and Snack cucumbers. A Baby pumpkin produces very long stems that need to be woven horizontally through the trellis.

Read exactly how to do this on the Baby pumpkin page in the shop:

Where can you find everything you need?

You will find the seeds, large Airpots and seed-starting mix in the shop. The good-value Climbing veg seed bundle is there too:
Have fun in your Makkelijke Moestuin!

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