How do tomato or lettuce seeds know when the temperature is right for germination? Well, this question will remain unanswered for now. We just know that it’s important that seeds have the right temperatures for germination. Germination temperature usually means soil temperature. During the day, soil stores heat. At night, soil releases heat into the atmosphere.

The University of Nebraska Video included below advocates for planting when soil temperatures are 10 degrees F (about 5 degrees C) above minimum germination temperatures. This concept is supported in our chart.

Seed Temperature Germination Chart

Source: Mostly from University of Oregon. Other information from other sources.

CropGermination
Minimum Soil
Temperature (°F)
Germination
Optimum Soil
Temperature
Range (°F)
Germination
Maximum Soil
Temperature (°F)
Days to
Germination
at Optimal
Temps
Asparagus5060-859514-18
Bean, lima6075-85854-10
Bean, snap6075-85954-10
Beet4060-85954-10
Broccoli4060-85957-10
Brussels sprouts4060-85953-10
Cabbage4060-85955-10
Carrot4065-85956
Cauliflower4065-85954-10
Celery4060-709510
Chinese cabbage4060-85954-10
Collards4060-85955-10
Corn5065-951054-10
Cucumber6065-951055-7
Eggplant6075-859510-15
Endive/Escarole3560-758510-14
Garlic3565-85957-14
Kale4060-85955-7
Kohlrabi4060-951055-10
Leeks3565-85958-16
Lettuce3560-75852-10
Muskmelon6075-951054-10
Mustard3560-75854-6
Okra6085-951057-12
Onion3565-85954-12
Parsley4065-85955-6 weeks
Parsnip3565-75855-28
Pea4065-75855-7
Pepper6065-75957-10
Pumpkin6085-951054-10
Radicchio3560-75855-7
Radish4065-85954-10
Spinach3565-75756-14
Squash6085-951057-10
Swiss chard4065-85957
Tomato5065-85955-7
Turnip4060-951053-10
Watermelon6070-951054-10

Our dilemma of germination temperatures of tomato or lettuce seeds is answered, as well as for many other vegetable gemination temperatures.

Video – Vegetable Soil Temperatures

Comments

Leave a Reply

More From Gardening Calendar

Eastern White Pine Uses

Experience the warmth, comfort, and stimulation of white pine uses, including clearing airways, boosting immunity, and treating common ailments with its rich vitamin C content.

On Planting Daffodil Bulbs in the Fall

If you are fairly new to bulb planting, I suggest that you start with daffodil bulbs. Very few creatures will bother these bulbs. They do well in almost any situation, and they increase their number each year. Tulips, hyacinths, crocuses, and other tasty bulbs are more difficult. Greetings fellow gardeners,

Ikebana Workshop – Notes from the Old Ottawa South Garden Club

from Old Ottawa South Garden Club Join the Old Ottawa South Garden Club for a workshop on Ikebana—a traditional Japanese art of flower arrangement by Elizabeth Armstrong, Second Associate Master in the Ohara School. Learn about its history and create your own arrangement with help from Elizabeth and Patty McGaughlin. Next meeting on April 9th to learn about easy-care, hardy perennials and lazier gardener methods.

How to Grow and Care for a Lantana Plant

Grow beautiful, low-maintenance lantana for your home or garden with the right materials and tips. Lantana plants are easy to start from seed and suitable for growing in containers indoors or outdoors. Learn how to start, repot, and care for lantanas today!