As summer’s heat lingers, the transition to fall planting can feel like a challenge. However, the cool-weather vegetables we look forward to—such as broccoli, kale, radishes, and salad greens—thrive when they mature in cooler conditions. Getting seeds started in hot weather is tricky, but these six tips will help you launch your fall garden with success.
1. Chill Your Seeds for Better Germination
Refrigerating seeds before planting mimics the natural conditions needed for them to sprout. Simply place your seed packets in an airtight jar and store them in the fridge at around 38°F (3°C) for a couple of weeks. This method is particularly effective for seeds meant for fall gardens, as it encourages germination by simulating spring-like conditions. If your seed collection is large, you can dedicate a small section of your fridge to those seeds designated for autumn planting.
2. Prime Seeds to Speed Up Germination
Some seeds, like spinach and beets, benefit from priming before planting. Soak seeds in room temperature water for about 12 hours. Then, spread them on a paper towel, keeping them moist and sealed in a container for a day or two. This jump-starts the germination process and makes seeds more heat-resistant. For beet seeds, rinse them in water every 30 minutes for 3 hours to remove natural inhibitors and encourage faster sprouting. Primed beet seeds typically germinate in 4–5 days, compared to 7–12 days for unprimed seeds.
3. Start Slow-Growing Vegetables Indoors
Vegetables that require a longer growing period, such as cabbage, chard, and kale, can be started indoors to avoid the hottest part of the summer. This method gives them a head start and allows you to transplant them to the garden once they have a few sets of leaves. Move them to a shady area once they sprout to keep them cool, and when
conditions are right, plant them outside.
4. Use Ice to Keep Seeds Cool
For fast-germinating crops like lettuce, radishes, bok choy, and cilantro, try the method of direct sowing with ice. First, chill the seeds in the refrigerator, then sow them in the evening. Scatter ice cubes or crushed ice over the seeds to help keep the soil cool and encourage germination. Cover the seeds with a shade cloth to prevent heat exposure. You can add more ice or water the next day if needed. This method helps prevent seeds from entering dormancy due to heat.
5. Plant in a Paper Grid for Better Moisture Control
If you’re direct-seeding crops like turnips, beets, or carrots, consider planting them in a paper grid made from wet newspaper strips. This method keeps soil moisture consistent and suppresses weed growth. Lay out the wet newspaper in strips (about 6 sheets thick), then plant your seeds between the strips. This setup helps keep the soil cool and moist, while also allowing for easier watering and thinning of seedlings.
6. Use Shade Covers to Protect Young Seedlings
Young plants and seedlings need protection from the intense summer sun. Shade covers filter out some of the light, helping your plants focus on growing strong roots rather than struggling to survive the heat. While this method reduces the amount of direct sunlight, it still provides sufficient light for healthy growth. As the weather cools, gradually remove or lighten the shade covers, allowing your plants to flourish.
By using these techniques, you’ll create optimal growing conditions for your fall garden, ensuring strong seedlings and a successful harvest.