I’ve been growing peanuts in my garden in the Far North of New Zealand for three seasons now. Over that time, I’ve learned a lot about growing, harvesting, processing, and eating them on a small-ish scale.

Since the publicity around the Pics peanut-growing trials, a number of people (including me) have picked up this strange little plant and given it a try too.

Retailers have figured this out and are (in my opinion, and being frank) taking the piss. Last year I saw peanut plants at Bunnings selling for $17.50—each!

Let me be really clear: when fully-processed peanuts are $8/kg in the supermarket and a single plant costs over twice that, you are never going to make any kind of useful return off that plant. This post will show you how to do it a little smarter.

Peanuts are fun and interesting to grow. They are legumes and therefore nitrogen fixers, meaning they’re good to include in a crop rotation. There are things you can do with them fresh-outta-the-dirt that you can’t do as well with a pack from the supermarket.

But they won’t save you money, and they might take a fair chunk of your time before you get to eat them.

There will be areas of New Zealand that can’t grow peanuts. They need full sun and frost-free conditions for 5-6 months. But there are also areas (particularly north of Auckland) that can grow peanuts, and if you’re interested in them and have the right climate, then they’re definitely worth experimenting with.

So, after three seasons of growing peanuts, what have I learned?

Sourcing peanut seed

It’s weird to put a peanut into some soil and grow a plant. Each year I am stunned that it works, but that’s all you’ve got to do.

You want a raw peanut with its skin still on. There are different varieties but the one you’ll see most commonly is Spanish Red. That’s what I’m growing. You’ll know it by the red skin inside the shell.

You can find a bag of these in the supermarket; or find a seller on TradeMe like I did (who may or may not have sold me peanuts from the supermarket); or I have a limited number of seeds for sale this year. Head to the store to grab them.

I believe there’s also a black peanut floating about, but I haven’t seen them for sale so far this year.

How many peanuts should you grow?

It all depends on what you’d like to do with them, and how much space you have available. The truth is every year I’ve grown them, peanuts have been really variable. Some plants have up to 30 nuts on them, some have none at all!

Germination can still be a little patchy, and inconsistent. So far, that’s always been part of peanut growing for me. I plant more seed each year, trying to work out the balance. Next season, I’ll be planting 120 peanuts. The rest of my seed is in the store for sale.

In my first year, I got a snack of roasted peanuts + seed for the next year from planting 30 seeds.

Year two, I got enough for a batch of peanut peanut brownies (+ seed for the next year). I would have planted closer to 100 seeds, but many rotted or germinated before I harvested them.

Last season was pretty close to a perfect one. I got two jars of peanut butter (+ boiled peanuts, and seed stock). That would have been around 180 seeds.

Sowing peanuts

In warmer areas with a long frost-free window, direct sow from mid October to early November. It needs to be quite warm—warm enough to be planting things like cucumbers and eggplants—but with enough runway to give you 5 months of growing time before frosts begin.

In my garden, most plants don’t start dying back until early May, so that leaves us plenty of time.

Push the peanut down into the soil to the depth of your first knuckle, cover with soil, and water in. Rows should be around 30cm apart, but plants within the rows can be about 15cm apart.

If you have a shorter growing season, you can try sowing them indoors earlier (August-September) in pots. It pays to give them a lot of space. Ideally one seed per 10cm pot.

Transplant outside in late October-early November. The countdown to harvest begins when you sow the seed (5 months), but they will need a lot of space if you’re going to do this for very long, and I don’t think they love being transplanted.

When transplanting, you can probably plant them a little deeper, burying the stems. That would mean you don’t have to be as attentive with the mounding step below; or mound anyway and see if it improves yield.

Maintaining peanut crops

Once the plants begin flowering, it’s time to mound them with soil. It’s not vital to their survival, but does seem to give you a better crop.

Pile the soil from between the rows up on to the plants to cover the main stems, as per potatoes.

Mulch around plants and between rows (I use dried lawn clippings) once the plants bounce back. They’ll quickly grow to shade out the space.

Water at least every second or third day for the first couple of months, but can be eased back to at least weekly over the following 3 months when peanuts are actively developing.

Harvesting peanuts

Lift with a fork as per potatoes. It’s hard to tell exactly when because die-back won’t be consistent over your crop, but it should be roughly 5-6 months after you sowed your seeds, and before the first frost.

If you wait too long, the nuts will begin either germinating or rotting underground. It’s not always evident from above the soil.

Most years, one or two of the plants will begin to die back earlier. That’s the best visual indication I’ve had.

Pull any yellowing plants immediately, then leave it another couple of weeks and pull the rest. Around mid-late April for us. Most years we have had a big storm around then and I’ve found it’s best to get the crop out ahead of the storm.

Drying peanuts

If you’d like to try boiled peanuts (and I’d recommend it), you can skip the rest of this and eat them fresh from the garden.

By far and away, this is the best reason I know of to bother growing peanuts yourself.

But if you’re planning to make peanut butter, roasted peanuts, or just store your peanuts for any length of time, then you’ll need to dry them.

Leave the peanuts on the plants, and allow plenty of airflow. You can lie them flat on a drying rack or shelf; or hang them in bunches of plants with the leaves hanging down. A dark, dry place is best.

It’ll be at least 2 weeks, but as long as they have the airflow, they can be left for months before processing further.

Saving peanut seed

Choose peanut seed from your best-performing plants. Over time, the genetics of your crop will adjust to your own conditions, providing better harvests.

I look for plants which are dripping in a large number of large nuts. I put them aside and then choose the best nuts from those plants to save for seed.

Basically, keep the best seeds from the best plants aside. In theory, those nuts have the best genetics, performing well under your climate and soil conditions. Within three seasons I’ve seen improvements within my germination and yield. You will too.

Remove the shells and store the raw peanuts in an airtight container in a dark, cool, dry place until next season.

Processing peanuts

This is where the real work of peanuts lies. Roughly, you need to:

1. Remove peanuts from the plants.
2. Crack hard outer shell and collect your peanuts.
3. Roast (some people blanch) raw peanuts, and allow to cool.
4. Remove papery skins.
5. Use your peanuts.

The outer shells will be dry and crunchy, which makes them a bit easier to get into. They make good carbon matter in composts and worm farms.

Once you’re through the shells, the papery skins need removing. First, lightly roast them (5 minutes at 140ºC is sufficient). Once they have cooled, they can be agitated in a clean tea towel, and sifted to remove the skins.

I say that like it’s easy, but they really need bashing. I found doing the sifting outside on a windy day was helpful. The wind helped carry away the skins as I shook the sifter.

In regards to the sifting, it helps to have something with bigger holes than your average kitchen sieve or colander. With 2kg of peanuts to process this year, I went and purchased something specifically for the job.

I think it might be an air fryer basket maybe? I found it at a dollar store in Rotorua. Worth keeping your eye out for something suitable if you’re planning a big peanut grow. Check dollar stores, emporiums, and op shops.

When all is said and done

If you made it this far you might look at your life and consider how much easier it would have been to just buy the bag of fully-processed peanuts at the supermarket. If you do, you will think this every year.

But once you’re here, you can finally use your peanuts. You can roast them, bake with them, or—if you grew a lot—make your own peanut butter. For the record, you need about a kilogram of peanuts for a 400ml jar of peanut butter.

Peanuts take a really long time, but they’re not demanding up until that final processing step. I note with interest that the Northland Pics peanut trials concluded that “developing more efficient small-scale processing methods could make local production more viable.”

I definitely agree. I don’t know if I’ll ever grow a crop big enough to send to a processor. But I do know what I processed this year was about my limit of how much I’m willing to tolerate processing by hand.

Growing peanuts is easy and fun. They’re weird little plants that are mostly happy to just do their thing through the long summer. Definitely a crop worth playing with if you enjoy eating peanuts and want to grow something new and interesting this year.

Remember if you’re keen, there is a limited number of seeds for sale in the store.