Direct seeding

Between winter holidays, work and taking courses, I didn’t have time to start many seeds this winter. But fortunately I can still start plants from seeds outside!
Nasturtium seed



The pros and cons of direct seeding

Direct seeding is great method for procrastinating gardeners: it gives us another crack at starting plants from seeds. And yes, for northern gardeners, the time for direct seeding is May and June. The soil temperature has warmed up enough for most seeds.

Other advantages of direct seeding include:

  • Saving money. Direct seeding is more economical than buying transplants
  • Saving time: You don’t need to harden off plants (i.e. adapt plants to outdoor conditions)
  • Better plants. Some plants grow better when not transplanted, especially plants with long taproots. These plants include larkspur, cucurbits, celosia, poppies, bachelor buttons, cosmos, dill, grasses and sunflowers.


There are a few disadvantages:

  •  It takes longer to bloom than transplants started indoors. However Ramon Gonzalez, @MrBrownThumb, the seed guru, points out that many direct seeding plants catch up with transplants.
  • You will need to thin out direct seeded plants to provide uniform plant spacing. A tough one for many gardeners who hate to lose a plant!


When do you direct seed?

What is critical for seed germination is the SOIL temperature. Soil temperature can be easily measured with a meat thermometer or a compost/soil thermometer. To get the average soil temperature, measure the soil first thing in the morning and in the middle of the afternoon.

Tomatoes and peppers, and other any plants that takes time to mature, are best planted out as transplants. Happy seeding! And please, share your seeding stories.


Germination temperatures for Vegetables

Vegetable                           Best soil germinating temperature C (F)

Bean                                       16-30             (61-86)

Beet                                        10-30             (50-86)

Cabbage                                 7-35               (45–95)

Carrot                                     7-30               (45-86)

Cauliflower                            7-30               (45-86)

Celery                                     15-21              (59-70)

Corn                                        16-32              (61-90)

Cucumber                              16-35              (61-95)

Eggplant                                 24-32            (75-90)

Lettuce                                   4-27               (39-80)

Onion                                      10-35            (50-95)

Parsley                                   10-30             (50-86)

Parsnip                                   10-21             (50-70)

Pea                                          4-24               (39-75)

Pepper                                   18-35             (64-95)

Pumpkin                                21-32            (70-90)

Radish                                     7-32            (45-90)

Rutabaga                                16-30           (61-86)

Spinach                                  7-24             (45-75)

Squash                                   21-35            (70-95)

Tomato                                   16-30           (61-86)


Adapted from

Alberta Agriculture and Rural Development: Soil Temperature for Germination

Alabama Cooperation Extension Systems: Soil Temperature Conditions for

Vegetable Seed Germination


Germination for flowers & herbs

Flower                                 Best soil germinating temperature C (F)

Aster                                       21                   (70)

Borage                                    18-21             (65-70)

Caraway                                 18-21             (65-70)

Celosia                                    24-27            (75-80)

Cosmos                                   21-24             (70-75)

Dill                                          21-24             (70-75)

Fennel                                     18                   (65)

Larkspur                                15-20             (59-68)

Lobelia                                    21-24             (70-75)

Nasturtium                            18-21             (65-70)

Phlox                                      13-16             (56-60)

Poppy, Iceland                       18-21             (65-70)

Poppy, Oriental                     18-21             (65-70)

Sunflower                              21-24             (70-75)


Information adapted from Harris Seeds Cultural Guide.




Written by Cristina da Silva
Thursday, May 30, 2013 in Plants & Soils

Social Sharing Share 'Direct seeding' on Delicious Share 'Direct seeding' on Digg Share 'Direct seeding' on Facebook Share 'Direct seeding' on Google+ Share 'Direct seeding' on LinkedIn Share 'Direct seeding' on Pinterest Share 'Direct seeding' on reddit Share 'Direct seeding' on StumbleUpon Share 'Direct seeding' on Twitter Share 'Direct seeding' on Add to Bookmarks Share 'Direct seeding' on Email Share 'Direct seeding' on Print Friendly


  1. Wow great blog post! I love how you put the charts in there, great facts, very accurate! Any tips for our rookie direct seeders?

Leave a Reply to Direct Seeding Cancel reply

Your email address will not be published. Required fields are marked *