Introduction
Here’s something I wish I’d known earlier in my gardening journey—September is a hidden gem for gardeners in the Netherlands. What you plant now will shape your garden’s success next spring. I remember my first few years of gardening, I’d let September slip by, thinking the season was pretty much over. I’d already harvested my summer crops, and my tools were stored away, waiting for the next warm season.
But then I realized something—I was missing out on one of the most important times of the year. September is prime time for sowing, and with the right crops, you can give your garden a head start for next spring. Whether you’re dreaming of fresh veggies or a colorful flower bed, this is the month to get it right. Let me walk you through the seven essential vegetable crops you should be planting right now, and some insider tips to help you nail it this year.
Why September is Important for Dutch Gardeners
Let’s start with the basics—why is September so important? In the Netherlands, we’re blessed with mild autumns that give many crops just enough time to establish before the winter chill really sets in. These crops can then overwinter, developing strong roots and waiting for the first signs of spring to burst into life.
What does that mean for you? Less work come spring, more reliable harvests, and earlier blooms. Not to mention, it’s a great way to keep the gardening momentum going when others are hanging up their tools for the year. The key is knowing what to sow—and that’s what I’m here for.
The 7 Essential Crops to Sow in September
1. Spinach
Spinach is one of my favorite crops to plant in September. Why? Because it’s hardy, fast-growing, and perfect for the cooler autumn weather. You can sow it directly into the ground, and it’ll give you baby leaves in just a few weeks. The real magic happens when the weather gets cold—spinach thrives in cool temperatures, and with a little protection, you’ll be harvesting well into the winter.
Tip: If you’re feeling fancy, try planting a few different varieties like 'Winter Giant' or 'Bloomsdale' for a continuous harvest.
When: The whole of september
2. Radishes
Radishes are another quick-growing crop that loves the cool weather of September. They mature fast—sometimes in as little as 25 days—so you can get a few rounds in before the frost hits. I still remember my surprise when I pulled my first radish from the soil, bright red and crisp. It’s one of those crops that gives instant satisfaction.
Tip: Plant radishes alongside your spinach. They grow quickly and can be harvested before the spinach really needs the space.
When: The first, second and third week of september
3. Lamb’s Lettuce
Lamb’s lettuce, is a must-have for any fall garden. This leafy green is not only delicious in salads, but it’s also incredibly cold-tolerant. I often plant a patch in our front yard garden where it can grow undisturbed. Come December, I’m still picking fresh leaves when everything else has gone dormant.
Tip: Lamb's lettuce can be slow to germinate, so be patient. It’s worth the wait when you’re harvesting fresh greens in the dead of winter.
When: The first and second week of september
4. Garlic
This is the crop that pays you back in the long run. Plant garlic cloves in September, and by next summer (July), you’ll have a bounty of fresh, homegrown garlic. There’s something special about watching those first green shoots poke through the soil in the spring after months of waiting.
Tip: Use a high-quality variety like ‘Thermidrome’ or ‘Vallelado’ for the best results, and don’t forget to space them properly!
When: The last week of september
Learn more about growing garlic
5. Broad Beans (Field Beans)
If you want to get a head start on next year’s harvest, broad beans are the way to go. Sow them in September, and they’ll establish themselves before winter. Come spring, they’ll shoot up fast and be one of the first crops you can harvest. It’s a game-changer for impatient gardeners like me.
Tip: Make sure to protect them from harsh winter frosts by covering them with fleece or cloches if needed.
When: The last week of september
Learn more about growing broad beans
6. Spring Onions
Spring onions are another great crop to sow in September. They’re slow to establish but tough enough to withstand the winter months. When spring rolls around, they’ll be one of the first things you can pull from the garden.
Tip: You can plant them densely and thin them out as needed, using the thinnings in your salads and stir-fries. We multi-sow them 8 to 10 seeds in a clumb.
When: The first and second week of september
7. Kale
Kale is a powerhouse crop that keeps on giving. It loves the cool weather and can even survive frost. In fact, kale’s flavor improves after a frost, becoming sweeter and more tender. Plant it now, and you’ll have a steady supply of nutrient-packed greens all winter long.
Tip: Try different varieties like ‘Nero di Toscana’ or ‘Red Russian’ for a bit of variety in both flavor and appearance.
When: The first week of september
8. Lettuce (bonus)
Lettuce is one of those crops that’s often overlooked for fall sowing, but it’s perfect for September in the Netherlands. The cooler temperatures help it thrive, and you can enjoy fresh salads well into autumn. I love growing varieties like ‘Lollo Rossa’ or ‘Winter Density,’ both of which are perfect for this time of year. Lettuce grows quickly, so you can be harvesting tender leaves in as little as 30 days.
Tip: Rocket is great for a winter growing, adding some mild spice to your dishes.
When: To keep the harvest going, try succession planting—sow new seeds every two weeks until the weather gets too cold. If you have a cold frame or greenhouse, you can extend your harvest even longer.
Learn more about growing lettuce in the winter
Common Mistakes to Avoid
Even seasoned gardeners can fall into some common traps when sowing in September. The most important thing to remember is not to overcrowd your seedlings. It’s tempting to fill every inch of space with new plants, but giving them room to breathe is crucial for their success. Also, don’t forget to cover sensitive crops as the nights grow colder, especially if frost is in the forecast.
Extra Tips for Successful Sowing in September
- Prepare Your Soil: Before you start sowing, make sure your soil is well-prepared. Add compost or organic matter to enrich it and improve drainage.
- Use Row Covers: As the weather cools, use row covers or cold frames to protect your young plants from frost and pests.
- Succession Planting: If you’re planting fast-growing crops like radishes or spinach, consider succession planting every two weeks to ensure a continuous harvest.
- Protect from water: Some plants just can't handle to much water, like garlic. If there is a lot of rain forecasted, protect them with a low tunnel or simple temporary structure.
Conclusion
September is one of the last important months for Dutch gardeners, and with the right crops, you can set your garden up for a thriving spring. From hardy greens like spinach and kale to long-term investments like garlic, what you sow now will pay off in the months to come. So, dust off your tools, grab some seeds, and get planting—your garden will thank you for it.
What’s your must-sow crop for September?