Sunday, May 10, 2015

Moving Day for Leeks

I'm making my first serious attempt to grow leeks this year. Last year it was onions, something that I had never considered growing because I didn't think they were worth the space. My perception was that I couldn't possibly grow enough to meet my needs with the space that I had available. Well, I proved myself mostly wrong, from the time that I started harvesting spring onions in March until I used the last red onion in November I didn't have to purchase an onion. The 6 months that the onions occupied space in the garden, was well worth the investment. And had I grown some storage onions instead of exclusively sweet onions I probably would have been using homegrown onions even longer.

My success with onions last year made me want to add leeks to the allium lineup. Leeks require a longer investment in garden space, anywhere from 6 to 14 months in the garden. The advice for growing them in my mild winter climate is to sow seeds indoors in December or January or outdoors in January through March. Mature leeks should be ready for harvesting sometime in September. One of the advantages of growing leeks is that they can stay in the garden through the winter so harvesting can continue until about mid-March when they should start to bloom. The problem with that long time frame in the garden is that they can hog some serious space for a long time. But, there is a technique that can minimize the space that they hog for part of their time in the garden - growing in a seedbed and then transplanting the young plants to their final spot in the garden.

My foray into growing leeks started back on December 17 when I sowed seeds for Blue Solaise and Lungo della Riviera leeks into 4-inch pots, one pot for each variety. On February 14 I set the seedlings out in the garden, two rows of tiny little seedlings spaced about 1-inch apart. It's a bit difficult to see below, but they are the wispy little things at the top of the photo (almost invisible, not the seedlings with white bases), the rest of the seedlings in the bed are onions. Everything is covered with netting because the birds will pluck at anything green at that time of the year.

Ideally, the leek seedlings should be lifted and and set into their final positions when they get to be the size of a pencil, but some of mine got to be a bit bigger, more like the diameter of my forefinger. 

Leeks in their seedbed on May 9

Leeks on the right, onions on the left
The young plants were easy to lift and separate. I sorted them by size, the largest to go into a long term bed and the smallest to go back into the original space for harvesting young.

Leeks sorted by size
Using the seedbed method allowed me to grow a crop of cabbages in the space where the leeks might have been planted had I chosen to set them out at their ultimate spacing back in February. I used my usual amendments of compost, crab meal, sulfate of potash, and Azomite, plus an extra dose of nitrogen in the form of blood meal. I dug a small trench about 7 inches deep, sprinkled in some Mykos mycorrhizal fungi inoculant and placed the leeks four inches apart with their roots in the center of the trench.

I partially filled in the trench and then nudged the leeks into an upright position and finished filling in the trench.  I used Azos bacterial inoculant when I watered them in. Planting deep like this also eliminates a chore that would be required if I had set them into their final positions as little tiny transplants. The best part of a leek is the white portion of the shaft and the shaft will not turn white unless it is blanched. The traditional method of blanching is to hill soil up around the leeks as they grow or to start the leeks in trenches and add soil as they grow. Either way, you need to have a mound of soil sitting somewhere for hilling or filling and I don't have a convenient space for that. Transplanting larger leeks into a trench and filling it in may be more work at the time you have to do it, but in the long run it saves time and space.

I ended up with three rows of leeks, about 22 leeks per row, each row 9 inches apart. I'm not sure if they are too close together, the recommendation is to set them out 4 to 6 inches apart and I chose the closer spacing.

The smallest of the seedlings went into the space where they spent the last three months, the plan being to harvest them first as babies. When the onions are ready to pull then the space will have to be cleared to make way for fall and overwintering vegetables.

The only issue that I've had with the leeks so far is that they have been infected with rust - Puccinia porri. Rust in alliums is extremely difficult to control. There are no recommended organic treatments but I seem to be having some success with a 70% extract of Neem oil. It doesn't cure the problem but it does seem to slow it down. About 2 tablespoons of Neem extract per gallon of water sprayed about twice a week to start has been very helpful. The biggest problem with Neem extract is that it has a distinct aroma and flavor so it gives an off flavor to anything that it is sprayed on. I'm hoping that the rust infection will largely disappear when the weather gets warmer and drier, but even so, the parts of the leeks that aren't treated, the shafts, will be fine to eat.


  1. I think this is a good investment when you have room. I saw leek plants for $2 each leek at the Farm Store last week. Who'd buy that when you can get them in the market for less? Yours look so bulked-up (thick) for so early in the season; they look luscious. I've read that they aren't dependent on day length is that right? Having enough leeks around when wanted would be heaven indeed.

  2. I'm going to have leek envy this year. I added shallots to my alliums, but haven't put leeks back in years.

  3. Yum I see leek and potato soup and leek frittatas in your future. That's what I would do with them.

  4. I grew Leeks in earnest for the first time last year, and they were very good - definitely worthwhile. I had no pest damage at all, but a couple of the Leeks bolted due to the weather conditions. My soil is very sandy and dries out very quickly, which Leeks do not like. I had to water them very frequently. I don't like the sound of that Neem oil you have used! Hopefully your Leeks will have such a powerful aroma of their own that they will counteract it.

  5. You've got some fantastic looking plants there. They are a great vegetable and well worth it as you seem to pay a dollar a leek in california for what are usually substandard quality. I'm sure you'll get a great harvest. Your technique looks a little complicated though. I lived for many years in Wales where leeks are the national vegetable and you would hear little old ladies in the street talking about the quality of leeks available at different greengrocers so it was definitely an important issue. They really like long thin leeks with a lot of white stem. The way they do it on a home grown scale is to be use a dibber, usually a sharpened broken off old fork or spade handle. Go along a row and make a hole with the dibber about 8-0 inches deep and just drop your plant in. Then water in. Don't bother to fill the soil in as the watering in will settle the roots. The hole remains around the shoulders of the plant stays open for a while until rain or time will generally fill it in. That way no need to hill up as the hole will eventually fill in and be level with the soil and you get a long white stem. With the great plant starts you have I'd make a deeper hole so just the tops were exposed, result great long white stems. These are from me attempting to replicate in California

    1. Beautiful leeks! And thank you for the great advice, it sounds so much easier than what I did.

  6. Your leeks are beautiful. I'm sure you will find them rewarding. I haven't had luck growing them in raised beds, but when I gardened in-ground I used your method and 4 inch spacing was OK. I'm going to try them again this year using the technique described by prussack

  7. I love leeks, but have only tried them once before. I don't foresee trying them again soon ... in fact, I think this might be the last year for any kind of onions for me due to poor success in the past. But you are having great success with all of yours and I look forward to seeing the harvests!

  8. Your leeks are looking wonderful! I didn't realize that they should be started that early...I'm only growing a few, but have learned so much already from all of the mistakes I've made. I'll be putting those lessons to good use next year. This year, I'm just hoping I end up with something edible at the end of the season, small as it may be.

    1. I start that early only because the winters here are so mild, in a cold climate like yours it would be too early.


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