During the month of February, I break out the old seed starter kit to grow onions and leeks. In this article, I will focus simply on leeks. So, why do I start my seeds so early? Leeks have a long growing season. If you live in the north, you want to start them at least 8 to 12 weeks before your last frost date.
In warmer areas, you can start them about 3 to 4 weeks before you last frost date. In both cases, leeks can be planted when the temperature is above 40 degrees Fahrenheit (or 4.4 degrees Celsius.)
How to Grow Strong Leek Plants
In the past, I placed my seedlings in a sunny south facing window. However, the seedlings were always spindly. Five years ago, I made the best gardening investment and purchased a tiered plant lighting tower from Gardener’s Supply. (They have many different models to suit your budget and needs.) I highly recommend purchasing grow lights of some kind.
Watch my video here how I plant my seeds. Note, I will be mentioning onion seeds too.
Which Leek Seeds to Use
Before, you decide to plant leeks, consider whether you want to grow leeks that are known for the cold hardiness and longer maturity or you tend to be on the impatient side and want to harvest leeks early. Cold hardy varieties such as Giant Musselburgh, Blue Solaise, and American Flag have long days until maturity and have short thick stems. Their growth slows down around mid-October until early March.
Additionally, they can survive temperatures as low as 15 degrees as long as the plants have adequate mulch. Therefore, these leeks can be harvested at any time during the fall, winter or early spring if they overwinter.
Other varieties such as Varna and King Richard can be harvested during the summer. These varieties are not known for their cold hardiness. So, you could easily mix the cold hardy varieties with the summer varieties to harvest leeks all season long.
My favorite leek seed is Giant Musselburgh, an heirloom seed, which takes 100 days to mature. (Purchase heirloom seeds from one of my favorite heirloom seed companies.)
Planting Leeks in the Fall
As an experiment, I planted nicely established leek plants in the fall in one of my beds that I reserve for kale, collard greens and broccoli. Most of the leeks overwintered even though my garden is in Zone 6.
Since leeks are biannual, they flowered quickly as soon as the weather turned warm. If you want to collect the seeds, be sure to plant heirloom seeds in the fall.
I honestly didn’t expect the leeks to flower so quickly. When leeks flower, the stems get hard and woody. Next fall I will plant leeks and harvest them in early spring.
Leeks Help Keep Moths at Bay
I decided leeks are my new love, not because of their taste but they keep moths away from my kale, broccoli and other brasscia plants. Truth be told, I have no idea whether the flowering leeks or new spring leeks kept the pests away. Either way, I had one less bed to pick worms off my plants.
On a side note, I think the leeks keep those darn moths from destroying my plants better than garlic plants. Plus, leeks have a long growing life, unlike garlic which is harvested in the summer. I find that the moths are the worse towards the end of the summer–even into the fall. (Maybe invitations to the good eats in my garden arrive late in the moths’ mailboxes?)
This year we had several freezes and the cabbage looper worms were still alive. Why? Because their bellies were too full of my plants. The new rule in the garden is to disburse leek plants throughout.
As soon as the leeks are ready for planting, I promise to shoot another video on how to properly plant them.
Join the Conversation:
- Do you grow leeks?
- What is your favorite leek seed?