One crop I am such a fan of in my backyard garden is kūmara, and a great fun project for gardeners in late winter is sprouting kūmara slips! As kūmara need a long warm growing season, starting shoots off indoors nice and early means they have a head-start for a bumper crop, and is quite important if you’re in an area with a shorter growing season.
Kūmara slips are also known as shoots, tipu or tupu. They are a rooted portion of the vine, which we plant in the ground in Spring to grow us the kūmara tubers.
There are a couple of different approaches when it comes to getting them sprouted, but whatever you choose, make sure you’re using a medium size ‘mother’ kūmara which is in great condition with no soft spots or rots. One kūmara tuber can sprout many shoots. Each shoot will feed off the parent kūmara and eventually grow its own roots. Each shoot then becomes an individual kūmara plant.
Method 1 – Sprouting kūmara in a cup
This is my usual method which I’ve been enjoying for many years, mostly for the fun, but also the success I’ve had.
- Place a firm healthy kūmara in a glass of water, so that its bottom end is submerged. The bottom of the kūmara is the skinnier end which tapers off and may even have small thin little roots. The top end will likely be larger, fatter and have more eyes which is where the sprouts come from.
- Keep this on the windowsill or bench in a nice warm sunny spot. Warmth and light speed up the process, we’re aiming for 20°C.
- In 10 to 15 days, you will see shoots forming on the kūmara.
- Leave the kūmara in water until the shoots are around 20-30cm and the soil is warm enough to plant.
- Keep the water level up in the jar and keep water fresh by replacing it every week or so. Within a few weeks, roots will develop first and then sprouts will start to form.
Method 2 – Sprouting kūmara in a box
- Choose a box or a pot with drainage holes and fill it halfway with coarse river sand.
- Place a firm healthy kūmara into it.
- Cover with sand and water well.
- Keep the box in a warm space indoors or in a glasshouse. Again, warmth and light speed up the process, we’re aiming for 20°C.
- Ensure the sand stays moist but not wet, as shoots will grow up through the sand.
- Leave them growing in the box until they are around 20-30cm, and it is warm enough outside to plant them out.
What to do with Kūmara Slips
- Once you have sprouts that are around 20-30cm tall, remove them from your kūmara by carefully twisting.
- Remove the lower leaves from your slips and place them into a jar of water to develop a root system. They should grow quickly in just a few days.
- Again keep this water fresh, changing it regularly.
- Once your slips have formed a good root system, you are free to plant!
Ideally, the kūmara should not be planted in the garden until after your last frost and the soil is at least 18°C. This is usually around late October, but depending on where you live it might be earlier or later.
What if I’m too late?
If you run out of time to sprout kūmara slips, no worries you’ll find them at various garden centres mid-spring.
Koanga have a wide range of kūmara varieties to choose from, and a waitlist system, where you can sign up to be notified when their slips are available for purchase. We bought Kumara Candy and Reka Rawa last season and were very impressed with their flavour!
