Prof Walker shows
us how to go about planting root crops.
to my garden. I want to talk about root crops today carrots,
parsnips, beetroot, kumara and yams.
They've got one thing
in common: they like a deep, well-drained, beautifully structured
The kumara's been an
important crop in NZ ever since people have been here. It is subtropical
so it does best in the north where it's warmer. But I can grow it
down here in Christchurch on my slope.
I want to grow kumara, I get a disease-free tuber then I plant it
in moist sand or moist compost. I'll keep that moist and warm in
my glasshouse for about six or eight weeks, in which time it develops
these shoots. You may get as many as 30 of them from one plant.
I then plant them into
compost for two to three weeks till they develop a much better root
system and have a much better chance of catching on and growing
and giving us a good crop.
Carrots, parsnips and
beetroot are all sown as seed. I prepare the seedbed in very much
the same way. I'll show you today how I'd sow my beetroot.
all these crops I sprinkle fertiliser like Nitrophoska Blue at the
rate of a handful to a metre. Lighter for carrots because we don't
want too big a top for those. Beetroot and parsnips, I'm a little
Then I hoe it in thoroughly.
Beetroot seed are quite big. They don't need to be pelleted. Sometimes
you get big seeds containing clusters of three or four.
I like to sow them 2
cm, 3 cm, 4 cm apart. Of course, they'll still need a bit of thinning
remains for me to cover up the seed and also to use the back of
the rake to compress it to keep the moisture moving up.
Carrots can be sown almost
any time in the warmer areas, but in much of the South Island they're
mainly grown from early spring to January.
At this time of the year
I've already harvested my parsnips as they keep well in the freezer.
But in the case of the carrots and beetroot here, I've taken off
the tops already once, and they're beginning to grow away again.
And this is to delay them going to seed and becoming fibrous.
are another root crop that my family loves, especially roasted round
the joint. I shouldn't call them yams. Our scientists want us to
call them oca. They belong to the oxalis family and are not a true
yam. The true yam is a potato-like tuber.
If you want to grow good
yams, buy some good tubers from the supermarket and plant them just
like potatoes 50 cm apart in the row. The more compost they
get, the better, particularly if your soil isn't sandy. Then you
don't get too many of knobbly bits on them.
I've got here three new
cultivars that have been bred out at Lincoln. They've introduced
material from South America. They're trying to produce bigger ones
of different colour, hoping it will appeal here and overseas. Some
of these are so sweet, you can eat them raw.
on kumara, yams and potatoes