How to Harvest Walnuts + Storing Walnuts for Freshness

We’re now in mid-September, the temperatures are dropping and the squash are growing larger. As such, walnut harvest is right around the corner! Walnuts are staple fall harvest crops, along with apples, pears, and pumpkins.

Walnut trees grow very well all over the U.S., so it’s not uncommon to find one on your property or around your neighborhood. Generally, walnuts are ready for harvest around the end of September and early October, although this varies a bit depending on your region and climate.

While it takes a bit of work to harvest and prepare the nuts, once processed walnuts can store for up to one year! Which is fantastic considering that mature walnut trees easily produce a year’s worth of nuts each harvest.

In this article, I’ll explain how to harvest walnuts step by step and what needs to be done to store them properly so you can enjoy the harvest year round!

Black Walnuts Vs English Walnuts

There are two major types of walnut trees you might find or be growing, which are the Black and English walnut tree. They’re both deciduous trees that are quite easy to grow, and their nuts are both harvested the same way. However, the two actually have very different tasting walnuts, so it’s good to know which tree you’re working with!

The nuts from English Walnuts are most likely the walnuts that you’re familiar with, as these are the type that’s usually sold in stores. English walnuts have a more mild, nutty flavor while Black walnuts have a very strong earthy flavor.

In fact, when Black walnut trees are grown it’s more often for their wood than the nuts, which is also fragrant and quite sturdy. Black walnut trees are native to North America, so if you find a wild walnut tree in your area it’s most likely a Black walnut tree.

English walnut trees are actually native to the Middle East, but after many years of selective breeding by the Greeks to increase their nut size, they became quite popular all through Europe. These trees were brought over to the U.S. by the British, which is why we call them English walnuts. English walnut trees are often grown in orchards for their nuts.

Black and English walnuts look the same from the outside, however once you remove the outer husk, you’ll see the difference. Black walnuts are about 2 inches in diameter and have a thick dark shell where English walnuts have a light brown shell.

Leaves of an English walnut tree. 

When to Harvest Walnuts

Walnut trees produce their fruit over the summer and towards the end of the summer, they produce the nuts at the center. These will be ready to be harvested in early to mid fall, so typically at the end of September and the beginning of October.

If you live somewhere warmer, you’ll need to wait until early November for the nuts to be fully formed and ready for harvest.

However, if you had a very dry summer and the trees didn’t receive much water, this can stunt the development of the nuts and will lead to a later harvest. If you can, try to maintain constant moisture for the walnut trees or give them a thorough watering at the end of the summer to boost nut production.

When the nuts are fully formed, they’ll drop from the trees in their husks, which look like tennis balls. Sometimes, the husks will open up while they’re still on the tree and this is definitely a sign that they’re ready to go!

What Ripe Walnuts Look Like

Ripe walnut husks look quite different from the bright green, unripe husks, so the change in appearance is a really useful indicator of when to harvest walnuts.

The husks of the walnuts will become discolored and soft as they ripen, resembling beaten up tennis balls! They will go from bright green to a greenish-yellow color and as they soften, you’ll see large brown bruises on the husk.

Some ripe husks also have small brown dots all over them and this is completely normal. However, if the husk is completely brown and mushy, this means the walnut is overripe and the nut won’t be good.

An over-ripe and rotten walnut that has fallen off the tree. 

The fruit is still not ripe yet if the husk is a vibrant green or the husk is still very firm. With ripe walnuts, you should be able to press your thumb into the shell and leave a small dimple.

Walnut husks are hard when they’re first formed but they soften as the nut forms which also makes it easier to peel away the husk when you’re harvesting!

Sometimes, as the nut ripens, the husk will split and open on its own and this is alright to harvest, even if there’s some worms around the hull. Ripe walnuts also vary in size, so don’t discard any tiny walnuts if they seem ripe.

Harvesting Walnuts

Most of what you need to know about how to harvest walnuts is about knowing what they look like when they’re ready because the actual harvest is super easy!

One really important thing about harvesting walnuts is that you’ll definitely want gloves for this harvest! Walnut shells have potent tannins in their skin that deeply stains anything it gets on. Although, this means they’re great for natural dying!

When a walnut is completely ripe, it will drop from the tree on its own! Walnut trees make it super easy to know when and how to harvest walnuts, because at the time of harvest there’s tons of walnuts scattered on the ground around the tree.

Since they’re on the ground, many walnuts may be bruised or have worms on them. For the most part, this is okay and you can still collect them, as long as they’re not completely black and mushy.

Depending on what time you go to harvest, there may be walnuts that are ripe but haven’t fallen yet. You can take a long pole to hit the tree and shake out the ripe walnuts so you can collect as many at once.

Don’t try to pull walnuts off of the tree. The walnuts that don’t fall off the tree even after being shaken are definitely not ripe yet. These will need a few more days to ripen, so come back in about a week to harvest them.

Example of a ripe walnut that never fell off the tree, but the husk opened on its own.

Opening the Husks

The husk of the walnut is the yellowish-green outermost layer that you’ll find the walnuts in. As they ripen, sometimes the husks crack or completely open on their own, which really helps the harvesting process!

With low-hanging fruit, sometimes the husk will be cracked and you can simply take the shell right out. This is okay as long as the walnut is still on the tree, but if it’s just the hard shell on the ground, those can sometimes be rotten.

Unfortunately, you can’t compost all the walnut husks you take off. They contain a toxin called juglone which prevents plant growth, so this will contaminate your whole compost. This is why we often see walnut trees growing on their own, meaning they’re not a great choice for a food forest.

Stomping on the Husks

One of the most popular ways to open the husks is to lay out all the walnuts and just stomp on them. With ripe walnuts, the husks will be softened so they should break easily when stomped on.

Make sure you wear old shoes for this, because the walnuts will intensely stain your shoes!

After stomping, many of the husks will fall apart on their own. Those that don’t fully come off will be loosened and you can take them and peel the husk off by hand.

Here you can see how strongly walnut tannins can stain! Hands_after_hulling_500_black_walnuts / Elfbabe / CC 3.0

Opening with a Knife

You can also simply take a knife and cut open the husks. It won’t be hard to slice and remove the husks by hand since the husks are super soft, this process is just tedious and works best if you have a small harvest.

Driving Over the Husks

For a really large harvest, many people like to put all the walnuts in an old sack and slowly drive over it with their car. This is a really quick way to open the husks of many walnuts at once, but keep in mind that this will stain your driveway or road!

You don’t have to put the walnuts in a sack- you could just lay them out on your driveway, however it’s much easier having them contained in a large bag.

Remember that the husks are soft, so you don’t need much force with your car. It’s not advisable to drive over them so much that you crack the hard shells too, because the nuts need to be cured in the shells before you can store them.

DIY Husk Opener

Many gardeners that have been harvesting walnuts for years have developed a low-tech tool that’s really easy to create yourself and that makes removing the husk very quick.

Simply drill a hole in a flat piece of plywood or scrap wood that’s the size of a walnut without the husk. Place the wood plank with the hole over the bucket.

Set a walnut with the husk on top of the hole and push it through. By forcing it through the hole, the husk is pushed off and the shelled walnut falls into the bucket. This, of course, will stain the wood piece very strongly, but overall minimizes the stains since the walnuts go straight into the bucket.

Even though you have to pop the walnuts one by one, it’s actually very fast and makes the overall process pretty quick!

Washing the Shells

Once you get all the husks off, you probably still won’t be able to see the brown shells under all the black mush that exists in the layer between the outer husk and the shell. So, it’s necessary to give all the walnuts a thorough wash.

If you have a pressure washer, this will work very well and make this step go faster, however a normal garden hose works too!

The best method to wash many at once is to put all the walnuts in a bucket and fill with water. Lots of plant matter will come off from the first rinse, but also stirring the bucket and banging the walnuts against each other will help make it come off. Plus, with this method you can see if any shells float, which is a sign that the walnut didn’t fully form and can be discarded.

If you’re not using a pressure washer, you may need to do this two or three times over to get most of the plant matter off. You can also leave them to soak in water for several hours to soften up.

If you do have a pressure washer, there’s another method that many gardeners have used. Place all the walnuts on a rack or crate and spray them down with the power washer. You’ll probably need to stop and shake the crate to move the walnuts around, then continue to get all the sides.

However, keep in mind that you don’t need the walnut shells to be completely clean of plant matter. The point in removing the black mush is to reduce the moisture on the shell so that the walnuts can cure properly.

If left on, this moist plant matter could soften the shells or attract mold, which clearly decreases the storage time. Yet, if there’s a small amount in the grooves of the shell or tiny spots you can’t get out, this won’t be a problem!

Curing the Walnuts

You can open and eat the walnuts right away if you’re ready to, but they’ll have a slightly rubbery taste since they haven’t been dried. If you’re storing walnuts for later, then you definitely need to cure them.

Lay out the walnuts on a large pan or drying rack to let them completely dry. This can be done at room temperature or out in the sun. If you dry them outdoors make sure it doesn’t rain and keep your nuts protected from squirrels and birds!

It’s likely that they’ll be dried if you cure the walnuts for 2-3 weeks, especially if they’re drying in the sun. However, some gardeners think it’s best to cure them for at least one month, if not 5-6 weeks.

This is actually why walnuts are traditionally associated with Christmas! If you harvest in mid fall, by the time you cure and crack all the walnuts, they’re ready to enjoy for the holiday season.

This certainly depends on the temperature and humidity of where you’re drying, but the safest bet is to cure the walnuts for at least one month to ensure there’s no moisture and that mold won’t develop when storing.

Cracking the Hull

Any experienced walnut-harvester will tell you that it’s much easier to crack the hull with smaller hits than trying to smash it and having your walnut break into a ton of little pieces.

Cracking open the hard shell or hull of a walnut isn’t very straightforward, but once you’ve done several, you get the hang of it. This is precisely why the nutcracker was invented!

Similarly to how a nutcracker works, you can use a vise grip to lock in the walnut then slowly tighten it to crack the shell. Some people will also use a hammer and hit the nut a few times to crack it. You can also try just crushing with the flat side of a knife.

Regardless of how you try to crack the shell, be patient. Know that the harder you hit the shell, the more likely it will burst into all these tiny pieces that go flying all over. That’s both a pain to clean up and breaks the actual nut.

In any case, it’s quite hard to get the entire walnut intact and you’ll probably still have the walnut in pieces once you open the hull. If you really want the full nut, leave the walnuts to soak overnight, which will soften the shell.

Storing Walnuts

Once you’ve gotten all the walnuts out of their hulls, the hard work is done and you can store them easily for months to come. Walnuts can be stored at room temperature in an airtight container for up to one year!

Store walnuts in a cool place, ideally in a cellar or basement, although room temperature in a pantry works well. Make sure they aren’t exposed to any moisture so you don’t risk mold growing on them. Keeping them out of direct sunlight will also prevent moisture in the container or decay from light and will help the walnuts store for longer.

You can either crack all the shells at once and store the nuts so they’re ready for use, or you can store them in their shells and crack when you’re ready to eat them. If you store the shells, you should be totally sure that they’re all fully dried since you’re not opening them and can’t see.

Another way to store walnuts is to freeze them, which will make them last indefinitely. Freezing and then thawing nuts definitely changes their texture, so that’s something you’ll need to test out for yourself and see how the texture change affects your recipes.

Let the Harvest Begin!

It’s just about walnut harvest season and once it begins, you’ll have 2 to 3 weeks to collect all these nuts! Walnut trees provide an abundance of nuts, even as young trees but especially once mature.

Growing a walnut tree yourself is a great way to cultivate your own food or you’ve found a wild one, then you’ve got tons of free nuts! Walnuts are a great source of protein and essential fats. Plus, since they can be stored for months, one big harvest can leave you with nuts for months!