Kem Ormond’s vegetable garden: Kūmara growing guide, from planting to storage

The humble kūmara is a versatile vegetable with a wide range of delicious uses. Photo / Ross Setford

Kem Ormond is a features writer for The Country. She’s also a keen gardener. This week, she’s writing about growing and storing kūmara.

Are your kūmara in the ground yet?

Kūmara is a vegetable that friends are always asking me how to grow, and even though I have written about them before, now is a timely reminder of some of the do’s and don’ts when it comes to growing this favoured vegetable.

I have friends who grow fantastic kūmara, and I have spoken to them about their success and their secrets.

They all seem to have their own thoughts on how to grow them, so all I can suggest to you is if you decide to grow kūmara, take all the advice you can get and give it a go.

Kūmara definitely needs a frost-free growing season, so it’s best to plant them after the last frost in your area.

They usually take 4-6 months to mature.

Kūmara is absolutely divine when roasted, stuffed or used in a salad.

Like all gardening, you do need to prepare your kūmara bed well in advance.

First, you need to find a nice sunny spot, and the space needs to be generous.

Make sure the soil has had compost or sheep manure, or pellets added to it.

Mould up your soil into good-sized beds and then scoop out a furrow in each bed to plant your kūmara shoots into.

While kūmara shoots are readily available from your garden centres, if you’d like to propagate a cutting (I remember this from my school days), simply cut a mature kūmara in half and place the cut side down in a saucer of water.

Within a couple of weeks, you will notice green shoots appearing.

Once these are 10-15cm long, you can remove them from the kūmara and place them in water to root.

Place most of the cuttings into the ground, bending the bottom where the roots are into a “J” shape - this encourages the roots to travel horizontally along the soil and not bury themselves too deep.

Then cover the roots with soil and give them a good watering.

Some gardeners insist the planting direction should face north, and others that it should be east/west.

I will leave this to your discretion.

After you have planted your kūmara shoots, you need to water consistently, but avoid over-watering them, and mulch to retain moisture and control weeds.

You need to lift the foliage regularly as the vines grow.

This is because the stems naturally put down new roots where they touch the soil.

If you lift the foliage, the plant will put more energy into tuber growth rather than leaf growth.

And it is the big fat tubers that we want.

They will benefit from regular feeding.

Harvest your crop once the leaves start to yellow.

Cut back the foliage and then lift the kūmara carefully using a fork.

Then there is the process of hardening the skins and sealing them to keep in moisture, but keeping out the bad fungi and bacteria.

This also brings out more sugars, which gives kūmara that wonderful, delightful taste.

They need to cure for around five days.

I have a friend who spreads his on an old wire bed frame under the eaves of his workshop.

He places his kūmara out of direct sunlight and covers them with newspaper.

The heat from the concrete helps with curing.

Make sure you only store the good-sized kūmara.

Don’t wash them; just give them a gentle brush to remove the soil.

They love to be wrapped in newspaper (like a little comfort blanket) and storing them in an old wooden box is ideal.

Successful storage is about warmth, not humidity.

You need to check them regularly, as one bad kūmara will find the rest!

Don’t try storing in cardboard boxes, especially if storing in a shed or garage; the rodents, especially rats, will think you have left a picnic hamper out for them.

In the past, I have used untreated ply boxes; if stacking, you will need a top lid.

I have also used adapted wine pine boxes.

So, if your kūmara is not planted yet, get onto it and give them a go!