Sowing vegetables: the right temperature for precultivation

If you want to harvest delicious vegetables as early as possible, you should start sowing early. You can seed the first vegetables as early as March. Especially for species that set flowers and fruits late, such as artichokes, peppers and eggplants, you should not wait too long. Fruiting vegetables from warmer regions and exotic fruits, for example Andean berries, require high growing temperatures. Cabbage and leeks have lower requirements, leafy vegetables such as spinach and chard, but also the robust root vegetables like it rather cool. Lettuce in particular germinates only hesitantly at temperatures above 18 °C / 64,4 °F.

If you have sown in seed trays, the seedlings are “pricked out”, that is, transplanted into individual pots, as soon as the first leaves sprout. Then lower the temperature slightly (see below). The following applies: the less light, the cooler the further cultivation, so that the young plants grow more slowly and remain compact. If the temperatures in the cold frame or greenhouse fall below the above values, the risk of shoots increases, especially in kohlrabi and celery.

Vegetable seed germination temperatures

Cool preculture

(12 to 16 °C / 54 to 61 °F)

Fava beans (broad beans), peas, carrots, lettuce, parsnips, radishes and radishes, spinach

Continue cultivation after germination at 10 to 20 °C / 50 to 68 °F

Average Heat demand

(16 to 20 °C / 61 to 68 °F)

Cauliflower, broccoli, chicory, kohlrabi, tuberous fennel, chard, May turnip and autumn turnip, leek, parsley, beet, chives, celery, onions, savoy cabbage.

Continue cultivation after germination at 16 to 20 °C / 61to 68 °F

Warm cultivation

(22 to 26 °C / 72 to 79°F)

Andean berry, eggplant, bush beans, pole beans, cucumbers, melons, squash and zucchini, peppers, hot peppers, tomatoes, sweet corn.

Continue cultivating after pricking out at 18 to 20 °C / 64 to 68 °F)

The sowing soil should be fine-grained and low in nutrients. In stores you can buy special propagation soil, but you can also make such a growing soil yourself. Spread the seeds evenly over the soil. Large seeds, such as peas and nasturtiums, can also be sown individually in small pots or multi-pot plates, while fine seeds are better sown in seed trays. Press seed and soil lightly so that the germinating roots make immediate contact with the soil. On the seed package you will find information on whether the plants are dark or light germinators. So-called dark germinators should be sprinkled with a thin layer of soil, while the seeds of light germinators remain on the surface.