Hey there, garden enthusiasts! Have you ever planted kohlrabi seeds with high expectations, but ended up with leafy plants that just won't form those delicious, crunchy bulbs? You're not alone! I've been there too, and today, we're diving deep into why your kohlrabi might be refusing to bulb up, especially if you've sourced those seeds from 2014. Let's crack this!
When you plant seeds that are several years old, like those from 2014, you might encounter a significant drop in germination rates or vigor. Kohlrabi seeds, like most vegetable seeds, have a shelf life. Generally, seeds remain viable for two to five years, depending on storage conditions. Poor storage—such as exposure to humidity, temperature fluctuations, or pests—can drastically shorten this lifespan. What Happens Internally?
As seeds age, their internal hormones and nutrients decline. The embryo inside might not have enough energy to push through the seed coat or develop properly once germinated. This can lead to weak seedlings that are susceptible to diseases and less likely to form bulbs.
To avoid this, always opt for fresh, high-quality seeds from a reputable supplier. Fresh seeds not only germinate better but also produce stronger, healthier plantsing in new seeds each season is a small price to pay for a bountiful harvest!
Kohlrabi loves cool, moist soil with good drainage. It thrives in fertile, well-worked ground that's been enriched with compost or well-rotted manure. If your soil is heavy, clayey, or lacks essential nutrients, your kohlrabi plants might struggle to form bulbs.
**Tips for Improvement
Kohlrabi prefers cooler climates with temperatures between 60°F to 75°F (16°C to 24°C). can cause the plants to bolt—going straight to seed production without forming bulbs. If you're in a warm or hot region, consider planting kohlrabi during the cooler parts of the year or using shade cloths to lower temperatures.
Plant kohlrabi in the spring or fall to avoid the hottest summer months. In cooler climates, you might get a second planting window in late summer for a fall harvest.
Crowded plants compete for sunlight, nutrients, and water, which can hinder bulb formation. Kohlrabi plants should be spaced about 3 to 4 inches (7.5 to 10 cm) apart in rows that are 12 to 18 inches (30 to 45 cm) apart.
Consistent, moderate watering is crucial. Kohlrabi needs about 1 to 1.5 inches (2.5 to 3.8 cm water per week. Water at the base of the plants to avoid wetting the leaves, which can promote fungal diseases.
Keep a close eye out for pests like cabbage loopers, aphids, and flea beetles, as well as diseases like damping-off and clubroot. Use organic pest control methods and rotate crops to prevent disease buildup in the soil.
Kohlrabi bulbs are ready to harvest when they about 2 to 3 inches (5 to 7.5 cm) in diameter. Harvest early for the best flavor and texture. Larger bulbs can become woody and less palatable.
Use a sharp knife to cut the bulb at the base, leaving a bit of the stem attached. Be careful not to damage the surrounding plants.
