First Seeds To Start in Winter

Here in Canada, we are blessed with dynamic seasonal changes. This seasonal shift however does shorten our window for gardening. There are some vegetables that need a little extra time if you want to optimize their season. Ideally, Asparagus, Leeks, Celery, Artichoke, Celeriac & Rosemary  should all be started quite far ahead of your last expected frost date. 

These plants all need a bit more time to establish. They are slow to germinate or slow growing. With our short, Northern growing seasons, it makes sense to give these plants a head start & to make the most of the time we have. 

What Seeds Should Be Started Early?

Artichoke

• Start seeds 10-12 weeks before last expected frost date.
• Seed Spacing: 1-2 seeds per cell or every 2 inches in a bulk tray.
• Seed Depth: ¼ inch deep & tamp down for good soil contact. 
• Heat Mat: YES - Artichoke seeds germinate best at 21-25°C. Remove heat mat after germination.
• Thin to 1 plant per cell / 1 plant every two inches.
• Artichoke is a tender perennial & requires vernalization to flower in one season. Before transplanting, harden off plants for at least 10 days at temperatures of 5-10°C. This will trick the Artichokes into flowering in just 1 season. 
• Transplant out after all risk of frost has passed.

• Start seeds 8 - 12 weeks before last expected frost date.  
• Seed Spacing: 1-2 seeds per cell or 2 inch spacing in a bulk tray.
• Seed Depth:  ½ inch deep & tamp down for good soil contact.
• Heat Mat: YES - Asparagus seeds germinate best at 23-25°C. Heat mat can be removed after germination.
• Thin to 1 plant per cell / 1 plant every 2 inches
• Transplant out after all risk of frost has passed.
• Asparagus is a long-lived perennial & requires a permanent location in your garden. Asparagus beds can produce for 10-15 years or more.
• Healthy Asparagus beds take time to establish. Please do not harvest before the third year.

• Start seeds 10-12 weeks before last expected frost date.
• Seed Spacing: A few seeds per cell or every 2 inches in a bulk tray.
• Seed Depth: ⅛ inch deep & tamp down for good soil contact.
• Heat Mat: NO - Celery seeds germinate best at room temperature.
• Thin to 1 plant per cell / 1 plant every two inches.
• Transplant out after all risk of frost has passed.

• Start seeds 10-12 weeks before date of last expected frost.
• Seed Spacing: A few seeds per cell or every 2 inches in a bulk tray.
• Seed Depth: ⅛ inch deep & tamp down for good soil contact.
• Heat Mat: NO - Celeriac seeds germinate best at room temperature.
• Thin to 1 plant per cell / 1 plant every two inches.
• Transplant out after all risk of frost has passed.

• Start seeds 10-12 weeks before last expected frost date.
• Seed Spacing: 3-4 seeds per cell or every 2 inches in a bulk tray.
• Seed Depth: Surface sow & tamp down for good soil contact. Rosemary seeds require light for germination.
• Heat Mat: NO - Rosemary seeds germinate best at 12-16°C.
• Thin to 1 plant per cell / 1 plant every two inches.
• Transplant out after all risk of frost has passed.
• Rosemary is a tender perennial. Bring indoors for Winter.

• Start seeds 8-12 weeks before last expected frost date.
• Seed Spacing: 1-2 seeds per cell or every 2 inches in a bulk tray.
• Seed Depth: ¼ inch deep & tamp down for good soil contact. 
• Heat Mat: NO - Leek seeds germinate best at room temperature.
• Thin to 1 plant per cell / 1 plant every two inches.
• Transplant out in late Spring.
• Once established, leeks are very hardy. With some protection, Leeks can be left in the ground for Winter harvesting. 

Caring For Transplants

You’ll have these young transplants with you for a few months. Grow lights, a heated greenhouse or nice sunny windows are a must. We recommend turning trays every few days to prevent legginess if in a window. 

To nourish your transplants, we recommend watering with a liquid fertilizer every few weeks. We use an all natural liquid seaweed emulsion. Remember, when using any fertilizer on baby plants, use it at ½ the recommended strength, avoid the leaves & water in the evening.

For more information on hardening off & transplanting into the garden, read our article Caring For & Planting Transplants. 

It’d be our absolute pleasure to help you establish your family asparagus patch or enable you in making some home grown artichoke dip. Please let us know how it goes! For more information on "which seeds to start when" consult our Veggie Garden Guide spreadsheet. Good luck! xox