Grow corn salad for greens year round

Corn salad (Valerianella locusta) is one of those plants that have almost too many names. 

Where I live the plant is referred to as “Winter salad” or “Mache’”. But a quick search reveals names like common corn salad, lamb’s lettuce, feldsalat, nut lettuce and field salad.

And not too surprisingly, corn salad is a true cold weather – and even a winter – plant. 

If you have ever tried to sow and grow corn salad during the height of summer you’ll know what I mean. 

With its shallow roots, the plant may suffer from drying out and could have the occasional attacks from mildew. 

Fact remains, Corn salad is the favorite salad green in our household. This article will tell you all you need to know about this wonderfully hardy and tasty little plant.

As a bonus I will round off the article with my favorite way of growing corn salad.

Growing corn salad from seeds outdoors

Corn salad is a very easy plant to grow as long as you stay away from the hot summer months. 

You can sow corn salad seeds in your vegetable garden from January and onwards depending on your climate. Just make sure that the ground is frost free when you plant your seeds. When the soil temperature reaches 10 degrees Celsius (50 degrees Fahrenheit) or so your seeds will start to germinate. If the weather turns freezing cold, simply cover your garden bed.

Corn salad likes compost rich soil that can hold moisture while also offering good drainage.

Water the ground before you plant the seeds. Do not plant the seeds too deep. From my experience planting the seeds shallow and then covering them with a thin layer of soil works best.

I draw a line in the soil with my finger. I try to keep the depth to around 1 cm (0.4 inches).

I then water.

When the soil has absorbed the water I plant the seeds in situ (where they will grow). I am always generous and plant 3-5 seeds every 10 centimeters.

When I plant in drills (or rows) I allow ca 30 cm (12 inches) between the rows for growing space.

Pro tip: Do not plant the seeds too deep or the seeds will rot. It is better to plant too shallow than too deep.

Water regularly as corn salad doesn’t like to go dry. And when the leaves appear, make sure you water the soil and not the leaves. If you water the leaves you risk attracting mildew and pests.

When to sow the corn salad seeds

I sow in two main batches when I plant seeds outdoors:

Batch 1: January – April
I sow in smaller batches one week or so apart during the months of January – April for harvest continuous harvest.

Batch 2: August-September
I also sow in weekly batches in situ in August-September for harvest in November. This second batch will grow slower and the seeds will need longer to germinate. 

But be patient. This is normal.

Also, some of the August-September batches are not necessarily harvested the same year but are left over winter. It does however depend on the temperature as when first leaves sprout you ned to harvest before the first frost.

But planting corn salad late in the year will allow me to harvest lovely green leaves early spring the following year. 

I simply cover the plants during the coldest periods but you will be surprised how frost and winter-hardy the corn salad is.

Leaving the corn salad to flower and self seed

The plants left unharvested will bloom around the months of May-June if left alone.

These blooming plants will, in turn, self seed and give you many more corn salad plants by early September. 

Choose to harvest these plants from the month of October or leave them to overwinter to have plants to harvest next spring.

And if you leave some of these plants to bloom.. I am sure you can see how you can make sure to always have fresh greens to harvest.

I do recommend harvesting full plants and planting new seeds every now and then. It is always good to introduce fresh plants to your vegetable garden when you can.

Fun fact: This is also why some people believe that this annual plant is a perennial. This is however not the case. The plant is simply a prolific and successful self-seeder.

Growing corn salad indoors year round

It is quite easy to grow corn salad indoors year round and harvest tender leaves as they develop.

To grow the seed indoors simply scatter seeds in a container and cover them with soil.

The plant likes compost rich soil. Make sure to use a pot that will hold moisture while also giving good drainage. 

Remember to water regularly as corn salad does not like to dry out. 

The seeds will take longer to germinate during the darker months of the year. 

I do recommend using a plant light during the winter months.

Cultivate corn salad seedlings indoors

If you want to kick-start your growing season, you can of course plant seeds indoors to develop seedlings.

These seedlings can then be transplanted to your vegetable garden as soon as the ground temperature exceeds 10 degrees Celsius (50 degrees Fahrenheit).

Do make sure that you keep the root clumps intact. Ideally you transplant the entire contents of the pot.

If the seedlings grow too thick you have a happy problem. Simply thin out the plants by harvesting the leaves for eating as the plants settle and grow. 

How to harvest corn salad

Corn salad is harvested leaf by leaf or you can cut the whole plant. The leaves you harvest are eaten or treated as lettuce or spinach.

My favorite Hack to grow corn salad outdoors

Like many other gardeners I have to plan how I use available areas for planting and growing herbs and vegetables.

And this holds true for both indoors and outdoors.

When it comes to growing corn salad (and leaf greens in general) I have a system that works really well for me.

Step 1: Buy a sack of soil from you local garden shop
Choose a good quality soil with compost and good drainage.

Step 2: Prepare the sack of soil for planting
Preparing the sack is as easy as 1, 2, 3 and 4.

Plant corn salad in sacks of soil for better use of space

First we cut 3 strips to expose the soil. 

Then we push a sharp stick or instrument all the way through the sack to create holes for drainage.

Next we water the sack of soil until the soil is moist but not soaking wet.

Finally we use our fingers to make lines about 1 cm (0,4 inches) deep along the exposed strips of soil.

Step 3: Plant the seeds
Now we plant the seeds. I am quite generous and usually scatter the seeds along the strip.

If my seedlings grow too thick I will happily thin out the leaves by harvesting baby greens early.

When the seeds are planted I simply cover the seeds with the excess soil. 

Again, do not plant the seeds too deep. 

When the seeds are covered we gently water the the soil until moist.

Step 4: Keep soil moist and remember that the sacks are mobile
Now we wait until the seeds germinate and we can see the first leaves or cotyledons.

Corn salad seedling sprouting first or seed leaves
Seed leaves, first leaves or cotyledons.

I water regularly and make sure that the soil never dries out.

On really hot days I move the sack into part shade to avoid midday dry outs.

After all, if you are mobile you should use it.

And there you have it. 

First leaves showing after planting corn salad in sacks
First leaves – only 2 weeks since planting.

I usually have at least a couple of sacks of different salad greens on the go. 

I find that it is an excellent way to make better use of space during the growing seasons without having to claim it as a permanent vegetable garden.

After all, everyone loves a busy vegetable garden when it is green and growing.

And corn salad makes for nice variation from lettuce and other leafy greens that are more often grown in vegetable gardens.

Frequently asked questions

How long does it take to grow corn salad?
It will take corn salad approximately 35-70 days to mature. The plant is often planted in spring and in the fall. When you plant in the fall seeds will take longer to germinate and the plant will also develop slower.

Can you grow corn salad anywhere?
Corn salad is very resilient to cold and frost and can be grown in most climates. But if temperatures drop as low as -15 degrees Celsius (5 degrees Fahrenheit) you will need to protect the plants. 

How do you grow a salad all year round?
The simple answer is to grow corn salad. 

You can of course grow regular salad year-round in heated greenhouses. This is, however, seldom economical. 

Growing corn salad will allow you to harvest tasty green leaves year round with just a bit of planning and effort.

Does corn salad need full sun to grow?
Corn salad will grow faster if exposed to full sun.

But the plant will tolerate part shade and it may even protect the plant from dry outs during the hottest months.

Why does corn salad dry out so easily?
Corn salad has a shallow root system. Shallow roots mean that the plants absorb moisture from rainfall and watering quickly.

The plant is however not able to absorb water from deeper soil.

The good news is however that the shallow roots will make the plant bounce back quickly if you just water.

Meet the author: Mattias is an experienced gardener spending most of his free time on his knees among herbs, plants and garden vegetables. For the past two years he has been sharing gardening projects and how-to tutorials on the NordicLavender website and YouTube channel.