Tag Archives: onehunga weed

Garden lore

It surprised him to discover that gardening, for all its air of prelapsarian serenity, is furiously competitive, frequently indulged in by the envious, the deceitful, the quietly criminal.

The Pedant in the Kitchen by Julian Barnes (2003).

Onehunga weed or prickle weed in the lawn.

Onehunga Weed

Onehunga Weed

The greatest curse of the lawn is the prickly Onehunga weed. If you know you had it last year – prickles in the feet- now is the time to act. It will take several years to eradicate entirely, but it will get worse if you leave it. You want to break the cycle and stop it from setting seed in early summer. These weeds are annuals – usually they germinate in autumn, romp away in spring (right now, in fact), flower, set seed and prickles and die as lawns dry out over summer. If you only have a little, hand weed it. There are specific sprays developed for Onehunga weed (ask at your local garden centre). We prefer to let the grass grow considerably longer than usual and then follow up in two to three weeks time by cutting it very short – scalping it in fact. The growth stretches the Onehunga weed up and it does not survive being cut very short. Timing is of the essence – if you leave it too late, the prickles and seeds will be developing. Onehunga weed does best in poor conditions. It is not so good at competing in a lush, healthy lawn.

In the Garden this Fortnight: January 26, 2012

A fortnightly series first published in the Weekend Gardener and reproduced here with their permission.

The dreaded Onehunga weed needs active management

The dreaded Onehunga weed needs active management

Onehunga weed is that innocent looking but prickly interloper to the lawn which makes walking in bare feet a misery. It is an annual weed and the prickles are part of its seed setting cycle. We had an invasion of it in some areas and rather than spraying, we tried scalping the lawn just before Christmas. By scalping, I mean cutting on a very low level and removing all the clippings to the compost heap. We normally mulch the clippings back in to the lawn. The lawn looked patchy for the next few weeks but the Onehunga weed was gone – including the new crop of seed heads. There is a risk element to this approach. Had we then struck a prolonged period of high temperatures and sun, we would have had to have started watering the lawn or watched a dust bowl develop. Scalping a lawn in early to mid summer is not usually recommended. As it happened, we had plenty of torrential rain to green up the lawn again.

You can spray for Onehunga weed (though you need to do it earlier in the season before the plants flower and set prickles) but we are increasingly reluctant to use lawn sprays, leaning to the view that maintaining one’s lawn chemically is getting close to environmental vandalism. Recent research from Massey has found a new strain of Onehunga weed which is resistant to the usual lawn sprays -another warning, perhaps, about gardening strategies that depend on chemical intervention. The weed generally germinates in autumn and grows through winter to flower and die in summer. If you have a lush, healthy lawn, it will find it harder to get going in competition with established grasses. Lifting the mower a notch or two higher can help keep a lawn in better condition (a scalped or shaved lawn is never a healthy lawn) and we are big advocates of using a mulcher mower, thereby avoiding having to feed the lawn. Where we need to over sow or renovate areas, we use homemade compost rather than proprietary fertiliser. Our lawns don’t look like bowling greens but they are generally healthy and green.

Onehunga weed is shallow rooted so if you only have a small area of grass, you can hand weed it. It is always better to get in early before it spreads – which it will do at alarming speed if you ignore it.

This one is auratum Flossie - all the lilies are opening now
This one is auratum Flossie – all the lilies are opening now

Top tasks:
1) An emergency staking round on some of the top heavy auratum lilies. We grow a lot of these for summer fragrance and blooms. Because they are garden plants and not show blooms, we support the flower heads on neighbouring plants where possible, but some just have to be staked. Home harvested, fresh green bamboo stakes are less visually intrusive than bought bamboos stakes. We shun plastic stakes but will use rusty old steel on occasion.

2) The rose garden is looking tired. I have major plans for a renovation of this area in winter but will start by lifting and dividing some of the stronger perennials, potting them to planter bags and keeping them out of sight and under irrigation while they recover. It takes many more plants than anyone ever expects to furnish a garden which has been gutted out. I need to start now to have sufficient plants to do a major rework and replant in winter.

In the Garden November 27, 2009

• Try planting up simple pots as Christmas gifts but get them done now to have them looking at their best in a few weeks time. Punnets of annuals are ridiculously cheap to buy. Planted now, three small plants (plugs, they are called) will fill a pot which measures around 20 to 25cm across. I still remember my splendid summer combination years ago of blue ageratum and cerise petunias. Or you can find cheap herb plants if you want to give an instant herb garden. Ceramic and terracotta pots are inexpensive these days, especially the classic terracotta type despite the fact they still seem to be imported from Italy. This is a good activity to carry out with children and will go down well with grandparents as it shows thought and effort. The cheapest potting mix is fine for annuals but keep the pots well watered and protected from slugs and snails while they settle in.
• With summer coming, set the level on the lawnmower a notch higher. Cutting the lawn very short does not mean you reduce mowing. Instead it tends to stress the grass so the weeds move in.
• If you have onehunga weed in your lawn, you have left it late to spray it but it is the one really bad weed which we think justifies a chemical assault. It is the weed that puts tiny prickles into any bare feet that dare tread upon it. There is a targeted spray called, we understand, Prickleweed Killer which doesn’t kill off the desirable grasses. If there are any children in your life, get onto dealing to it this weekend as your first task. Do not let this weed go to seed.
• Apples will have set their fruit for the year which means that if you had a codling moth issue in the past which you have not done anything about, odds on the larvae are scaling the trunk now to reach the fruit, if they have not yet made the journey. This means it is too late for pheromone traps which are designed to catch the moth before it lays eggs. You will either have to put up with moth eaten fruit or resort to some insecticide spray. Apparently lavender bushes or nasturtiums planted below will discourage infestations in the future but we have yet to see proof of this. It may be worth a try but I would keep to lavender because it is likely that rampant nasturtiums will engulf your entire apple tree. Tipping new growths by hand will largely deal to the leaf curling midge which attacks the very ends. Unroll the leaves and you may find a small pink creature inside. You either nip them off or spray them.
• The end of this month means you are running out of time to plant kumara, yams and any other type of sweet potato. Give these priority along with tomatoes. Potatoes planted now will be a late crop so you don’t want to delay on these either.
• It is four weeks until Christmas so get quick maturing salad vegetables in this week for harvesting at that time. It is much nicer to head out and pick your own mesclun, rocket, microgreens and radishes.
• If you are a fan of monarch butterflies, you will need to get swan plant seed in urgently to get the autumn crop through to feed the late caterpillars. Real enthusiasts will also be sowing seed trays of zinnias, marigolds and other autumn crops of annuals to feed the butterflies.