The weather outdoors is cold and gloomy. Here on the coast it is altogether wet — the ground is sodden and squishy. Elsewhere, the first blankets of snow are falling, and the ground is freezing hard. Only the most spirited of winter gardeners are still making trips to the greenhouse, low tunnels, or raised beds at this time of year.
Winter doesn’t officially even start until the third week in December, and then it goes on for three solid months. It’s not very intuitive to think about starting seeds this early for the coming spring and summer. Yet some plants are so slow to start that December and January are actually prime times to launch seedlings for the new year. The sun is very low on the horizon, so starting winter seedlings requires certain equipment, most importantly artificial light.
The recommendations here are intended to produce seedlings that can be transplanted after a March 28 Last Average Frost date. That date is specific to south coastal BC, the Gulf Islands & San Juan Islands, and the US Pacific Northwest. The plants discussed here need plenty of time after transplant before they mature and set flowers or fruit. If your last frost date is at the end of April instead of the end of March, simply adjust forward by one month. On the other hand, if you live up north where the growing season is short and intense, starting early seedlings indoors will be key to success.
Remember — most crops grow fast enough that they can be direct sown much later as spring unfolds. Many of the crops listed here are perennials or biennials. A very early start may induce flowering in the first year of growth. Also — these seeds can all be started later in the year. There is no rule saying they must be planted in the winter. Let’s look at each one in turn.
This perennial cousin of the Aster benefits from an early indoor start from January to early February. This strategy is to induce blooming in the first year. Artichokes can be started much later in the year, but no crop will come until year two and beyond. Keep artichoke seedlings under very bright light so they remain stout and compact. The time to transplant is shortly after the last frost date, so that the seedlings experience a period of about 250 hours below 10°C (50°F). This cool period simulates winter for the plants, and triggers flower formation in the first season. Give the seedlings protection if hard frost is in the forecast during this critical stage.
The strategy with this perennial is to encourage strong growth in the root crown during the first years of growth. This allows the plants to become strong and well-established for years of productivity. Unlike artichokes, an early start is not going to produce asparagus in the first year — alas, not even in the second year of growth! For the first two years, the stems and foliage are allowed to simply grow and gather energy that is stored in the plant’s root system over winter. By year three, if everything is going to plan, asparagus plants should be vigorous enough to send up lots of stems for cropping. Anyone with first hand asparagus-experience knows that this tantalizing wait is worth every moment. Fresh, home-dug asparagus is a truly wonderful thing. As with artichokes, keep early-planted seedlings very brightly lit to avoid spindly growth and leggy stems.
These flowers (all members of the genus Aquilegia) are prime examples of perennials that, if planted later in the year, might not produce flowers in the first year of growth. Once again, that’s not necessarily a bad thing — the flowers will eventually appear in year two and onward. But for first year blooms, a really early start is key. Direct sow columbine seeds any time from autumn to mid-winter. The seeds can be started indoors, but it’s more complicated: Sow seeds in flats of moistened, sterilized seed starting mix, and place these inside plastic bags in the refrigerator for two to three weeks. Then sink the flats outdoors in the ground in a shady spot, and cover with glass or plastic. As seedlings appear, transplant them or pot them on. Germination takes 30-90 days. The flowers of columbine are followed by exotic looking seed pods which slowly split open as they dry in the summer. The pods are held upright, so the seeds inside are particularly easy to save for future planting.
Biennial plants like foxgloves (and indeed, beets and carrots) typically put on leafy foliar growth in the first year, and store their energy in some kind of swollen taproot. After the first winter, the plant uses that stored energy to flower and produce seeds. Most biennials have rather extraordinary flowers and copious seeds that would be difficult to produce from only one year of growth. For flowers the first year, sow foxgloves indoors very early, in December or January. Transplant two to three weeks before last frost. The seeds may take 14-21 days to germinate. If starting indoors, provide bright light and a soil temperature of 15-18°C (60-65°F).
This perennial plant is a bit like columbine in that it may not bloom in the first year from a spring planting. However, lavender is a very long-lived perennial that develops a woody stem over time, and seems to bloom in greater profusion from one year to the next. It maintains much of its foliage over the winter in mild regions, unlike columbine, which basically dies back to ground level. Lavender seeds germinate most evenly if seeds can be collected in the autumn and sown on the surface of a seed tray with bottom heat maintaining 4-10°C (40-50°F). The seedlings are then overwintered in a cool greenhouse or cold frame with good ventilation. Seedlings can then be potted on as needed.
Another method is to start the seeds indoors in February, planting seeds sparsely in a few pots with sterilized seed starting mix. Dampen the mix, press the seeds into the surface, insert the pots into plastic bags, and put them in the freezer for two to seven days. Let them come to room temperature on their own, and then use bottom heat as indicated above.
This cousin of the onion is very easy to grow, but leeks are famously slow. They have the appearance of a single chive for what seems like months. After transplanting them outdoors, they advance a little, appearing like unenthusiastic scallions (spring onions). But by harvest time, the stems have thickened significantly, and many leaves have formed. Some leeks are bred for summer and fall harvest, and a few varieties are bred for winter harvest. Start summer and fall harvest leeks from early February to March in flats indoors. Wait to start winter harvest leeks from March to mid-June in a humus-rich nursery bed outside, and then transplant. The optimal soil temperature for leek seed germination is 10-25°C (50-75°F). The seeds should sprout in 10-16 days.
Here is a richly flavourful member of the grass family that is usually considered a herb because of how it is used. Lemongrass thrives in the tropics, but it benefits from a really early start in our temperate region. The best strategy is to give plants a healthy head start indoors under bright lights. As soon as it’s warm enough in spring (nighttime temperatures must be consistently above 10°C (50°F)), the seedlings are transplanted into a warm growing area outdoors. As summer advances, the stems will thicken and the plants will eventually form hairy clumps to be harvested at the peak of the hot season. Technically lemongrass is a perennial, and a stubborn gardener might be able to lift plants for greenhouse growing over winter. The plants may slow to the point of dormancy, but this would make them even more productive in the warm seasons to follow. Otherwise, just treat it as an annual, and start with fresh seeds each winter.
Most onions are not fussy about timing, but they are all slow growers. Many breeds of sweet onions have been developed that form massive bulbs of 10 lbs or more, but these take special care. These competition-sized bulbs would need to be started no later than the first week in February. Use bottom heat to speed germination and then grow the seedlings on under bright artificial light to minimize legginess. After around six weeks, transplant individual onion seedlings into 8cm (3″) pots filled with rich compost. Keep them in a warm, very bright location until around April before transplanting them to a cold frame. Give each onion lots of room to grow, and support its leaves with wire tomato cages or some similar structure. Giant sweet onions like Ailsa Craig and Kelsae can be grown on in individual five gallon containers or in warm soil with protection from harsh wind.
A few types of chili peppers belong to the species Capsicum chinense. These include the fiery hot and famous Scotch Bonnet and Habanero types, both of which begin to show mature pods near the very end of summer. In poor years, the plants may not produce a single hot pepper. So the grower’s strategy is to start the seedlings very early. Some growers plant the seeds around Christmas, but January should be early enough. These wonderful chilies require a full 120 to mature — and that is from the transplant date. Depending on the weather, they should be transplanted in June, under cover or into a greenhouse where the extra heat will prove extremely helpful. Like lemongrass, these are tropical plants, so the strategy is to transplant them as young adults, as opposed to toddlers. In a good year, with lots of heat, they can be very productive plants.
As with some of the other seeds discussed here, most strawberry seeds will have improved germination after vernalization. That’s the process of planting them, covering the pots, and keeping them refrigerated for several weeks in order to simulate winter. Horticultural theory suggests that this aids in breaking the seeds’ dormancy and may produce a higher germination rate and more uniform sprout development. Many growers have great success simply planting the seeds in moist seed starting mix under bright lights, but success may vary from seed lot to seed lot. Either way, for fruits to develop in the first year of growth, it’s a good idea to start strawberry seeds from a really early start in January of February. The plants will grow from seeding at any time of year, but may not produce fruit until years two and three.
The category of perennial that eventually develop woody stems includes oregano, rosemary, sage, and thyme. These are all slow growing as seedlings. These are so slow that most greenhouse propagation is done by taking cuttings of adult plants and rooting them as clones. It’s more economical to produce these herbs from seed, but the grower has to factor in quite a slow start. If bright artificial light is available, start these seeds at the beginning of February, or even earlier. It may be possible to gently harvest some of the leaves around the time they are transplanted out in mid-April to early May. But the early start will produce a stronger root system and sturdier stems by the time cold weather rolls around in the fall, and that gives the plants a much better chance of making it through winter.