- If you have harvested potatoes with a nasty brown split and blemish inside tubers which look perfect from the outer (our Agria are particularly badly afflicted this year), Plant Doctor Andrew Maloy says the most common cause is a fungal blight. As the spores remain active in the soil, make sure you plant your potatoes in a new area next time where you have not grown solanums (potatoes, tomatoes, aubergines, capsicums etc) for several years. Fungal diseases are exacerbated by heavy soils, too much water and too little air movement so free drainage, full sun and space will reduce dependence on fungicides.
- Easter, like Labour Weekend, is a big time for garden centres – long weekends and the change of seasons gets people focussing on gardening. Quite often there are clearance sales of last season’s woody plants and if you are tempted by these, they may need some TLC to thrive. Water, water, water to combat our dry soils. Make sure the root ball is saturated because if it is very dry it can actually repel water, even after planting. That is why you soak the root ball before planting. Cultivate the soil well – don’t just dig a hole that fits the plant. Dig at least twice the size and break up clods of dirt well so the roots have some good soil to extend into. Make sharp cuts down the root ball if it is really congested, cutting through any roots which have wound round and round the pot or bag. Cut the bottom of the root ball if it has folded in to its planter bag (like an envelope). Resist the temptation to tease out the roots – you will do more damage than good. Put any fertiliser around the roots at the side, rather than sprinkling on top and mulch with compost.
- Sow your new lawns this weekend and over sow bare patches in existing lawns.
- It is time to do the big autumn clean up in the vegetable garden. Remove any badly blighted or mildewed plants altogether to reduce future infestations. Don’t dig them in and only compost them if you are very confident that you make a hot compost mix. Ditto any seed heads.
- Save seed of crops as you harvest – beans, peas, corn, tomatoes, capsicums, melons etc. Most experienced veg gardeners agree that saving your own seed is a most satisfying part of the cycle. Always save the seed from the very best, strongest, healthiest specimen not some poor thing that is hardly worth eating.
- There was an alarming news item at the weekend to the effect that fresh fruit and vegetable sales dropped by over 30% during our latest recession. While I hoped that this might be an indicator that more people were growing at home (it is enormously satisfying to walk briskly through the produce section at the supermarket without needing to stop because you are self sufficient), the fact that takeaway food sales increased massively tends to suggest this is not the case. So be virtuous and get out to the garden this weekend to plant winter vegetables while there is still a month or longer of warm weather to get them growing. All the brassica family except Brussels sprouts, winter leafy greens, broad beans and even a late crop of beetroot can be planted.
Tag Archives: in the garden this week
In the Garden: March 19, 2010
The rows of corn in the garden are interplanted with food for the butterflies here
- The push hoe is an invaluable tool but one best used in dry conditions when severed weeds can be left on the surface to wither. This means that our current dry early autumn conditions are still a good time to do a push hoe round. This week’s rain has only penetrated the top centimetre or so of the soil here and unless we get some gentle, steady rain over a few days we will remain dry a while longer. Hoeing also gently tills the soil and discourages the build up of liverwort and moss which you see on compacted ground. Keep your hoe sharp for best results – using a file on it is fine.
- Naturally everybody has heeded our oft repeated advice and rushed out to plant brassicas in abundance for winter. Keep an eye on the white butterflies which may be hovering around your plants and laying eggs already. The hatching caterpillars will wreak havoc on your baby plants. They will be less of a problem when colder, wetter conditions set in but you may need to take action now. If you don’t wish to use a proprietary insecticide, you can resort to common flyspray for a quick hit or one of the organic based oil sprays (up to 10 ml of light cooking oil and a squirt of detergent per litre of water). Thuricide is a bacterial spray that attacks the caterpillar gut and is effective and selective (only attacks the one target) – you can buy it from your garden centre. If you have a really heavy infestation, you may need to spray and then cover your crop with old net curtaining to prevent reinfestation.
- If you have cauliflower or broccoli maturing already, bending the outer leaves over the head is the practical and time honoured means of stopping sun burn on the edible portions.
- Start the autumn feeding round now while plants are still in growth and can absorb the nutrients. It is a waste of time and money to feed when conditions are cold in winter and plants are dormant or semi dormant. More is not better with fertiliser and if conditions are too dry, it can burn the foliage so keep to recommended application rates and preferably spread it immediately before rain.
- It is trimming time for formal hedges. We plan an Outdoor Classroom on the topic next week.
- It should be safe to sow grass seed for new lawns now although you may have to get the hose out if we get another dry spell. What you don’t want to happen is for the seed to germinate and then fry in sunny, dry conditions so keep an eye on it.
- We are enjoying a fantastic crop of sweet corn here and Mark, who harvests it only as required so it is a matter of minutes from being picked to being cooked, is warning that there is a veritable deluge of corn to come over the next two to three months. This compensates for the lack of onions and water melons this season.
In the garden: March 19, 2010
- Don’t be tempted to sow lawns until we have quite a bit more rain and the moisture has penetrated deeper down. If you scratch around the soil, you are mostly likely to find that it is as dry as a bone a few centimetres down. However, the more work you do getting the ground levelled and taking off successive waves of germinating weeds, the better your lawn will be when the grass seed germinates. We favour a mix of fescue and rye for lawns here though in reality there are now many other micro greens in our grass. We try and keep out flat weeds, onehunga weed, kikuya and paspalum but beyond that, as long as it is green when mown, we are resigned to our mixed colony. We prefer that to the constant application of chemicals necessary to maintain a pristine lawn.
- Root vegetable crops take longer to grow and mature so you have pretty much missed the boat on winter root veg but you can still plant the leafy harvests such as winter spinach, silver beet and winter lettuce along with the brassica family. It is the leafy crops which require most fertiliser so be generous with the compost or liquid feed. Vegetable gardening is like any form of cropping – you can’t keep taking harvests and expect the soils to remain fertile unless you keep feeding and replacing the goodness that is being stripped out. Using composts, green crops and manures is more sustainable than continually relying on proprietary fertilisers and also helps to build good soil structure and texture.
- Compost chicken manure before use because when fresh, it can burn plants. If you don’t want to compost it, at least leave it until it is mature. Seaweed can be spread directly onto the soil and does not need to be washed first. Horse, cattle, pig and sheep manure can be spread directly on the soil. You may prefer to compost all fresh manure or leaving it to dry for several months before spreading around edible crops.
- If you are not planting all your area in winter vegetables then plant a green crop as you take out the autumn harvests. At this time of the year, we recommend lupins, oats, ryegrass or mustard. We are trying vetch for the first time. You should avoid using lupins where you have been growing beans or peas because they come from the same legume family and it is wise to rotate crops.
- As cooler temperatures set in, mice will start to migrate indoors so make sure you have any seed you are storing in rodent-proof conditions.. A disused fridge in the shed is good or plastic containers for smaller quantities. However, while rodent proofing is necessary, some seed, including fleshy types, do not want to be sealed off from all air so you may need to devise some compromise if the plastic containers have a tight seal.
- If your strawberry plants have put out strong runners, these can be planted now to give vigorous cropping plants next spring. Strawberry plants are best replaced entirely every two years and some gardeners replant every year, using runners and divisions. If you plan to leave existing plants for another year, cut any runners off.
- If you enjoy the mass display of annuals, you can sow seed now for an early spring show. Pansies, cineraria, alyssum, lobelia and snapdragons are all easy and reliable. Hollyhocks get badly mildewed in our climate, alas. Some perennials such as aquilegia, wallflowers, carnations and gypsophila can also be done easily from seed. Use seed trays for much better results. Don’t delay on taking cuttings of perennials and fuchsias. Hydrangea cuttings are best left until winter now and treated as deciduous cuttings.
In the garden: March 12, 2010
- With temperatures cooling, particularly at night, conditions are good for gardening. Leave planting or shifting of woody trees and shrubs until later in autumn but you can turn your attention to clumping plants and perennials. Lifting overcrowded plants and splitting them up at this time of the year means that the plants can recover and re-establish before winter. This can avoid bare patches in the garden in spring which is particularly important for those who open their gardens. Always dig the ground over to loosen up the soil and add some compost or other soil conditioner along with a dressing of fertiliser. To reduce the shock to the plants, cut back the top foliage by about half and water the plants in well. Keep watering for a few days if we don’t get rain.
- While working with your perennials, you may want to try taking some cuttings from types which only grow from a few stems rather than forming a clump of many shoots. We demonstrated this in an earlier Outdoor Classroom but the rule of thumb is to use firm new season’s growth and to take off any flower buds or stems. We are about to do some gypsophila cuttings.
- Flaxes, astelias and grasses will respond very well to being divided at this time of the year but they need their tops cut back. The Mohican hair cut is not a good look but done now, the clumps will spring into fresh growth and cover that. Done later, you will have the ugly cut leaves until late spring.
- A sharp spade makes digging and cutting hugely easier. We sharpen our spades by securing them in a bench-top vice and using a file. Remember to only sharpen the side which faces outwards when you use it. Once you have used a sharp spade, you will appreciate just what a big difference it makes.
- In the vegetable garden, you are really too late now for Brussels sprout, leeks, carrots and parsnips but you can still plant Florence fennel, winter spinach, peas, winter lettuce and all the obliging brassica family.
- Gardeners in colder, inland areas should be thinking about starting the autumn hedge trimming round. The trick to timing is to allow the hedge to make a light flush of fresh growth only and have time to harden it slightly before the onset of winter stops all growth. Get a man in, was the suggestion of friends over dinner at the weekend. We own up to having just such a treasure here (and he is not Mark) who is a perfectionist when trimming sharp hedges, even using a string line to keep the levels straight.
In the Garden, March 5, 2010
Mark surveys his field of buckwheat, swan plants to the right
- This is the first year we have tried buckwheat as a green crop and we notice it has the added benefit of feeding the bees. Bees are critical for pollination so having a bee-friendly style of gardening can help counteract the well publicised problems with declining bee populations. We bought the buckwheat from Kings Seeds (www.kingsseeds.co.nz). Green crops are a time honoured method of restoring fertility to land which is repeatedly cropped and are just as relevant today for the home vegetable gardener as they were hundreds of years ago when readers may remember from school history lessons about early agricultural practices of leaving a field fallow.
- More than just a green crop, if you let the buckwheat go to seed, it can be used as bird food for hens or pigeons. Feed the whole seed head out and the birds will do the rest.
- It being March, the winter vegetable planting calls. Fresh vegetables tend to be quite expensive in winter so home produce can be economic as well as satisfying. If you are anything more than a dilettante, ignore the trendy advice to grow your vegetables all together in a style reminiscent of the herbaceous border. This means you can not possibly practice rotation where you alternate different types of crops through the same piece of ground. A green crop is followed by the greedy feeders such as potatoes and corn, followed by brassicas and leafy crops and ending up with the root vegetables which do better in soil which has not been freshly fertilised.
- If you can’t remember the sequence of crop rotation, it is good practice to always plant a different crop to the one just finished. This greatly reduces the chance of building up diseases in the soil and pesky pests in the surrounds.
- It is time to be festooning outdoor grapevines in netting to keep the birds out, if you want a crop. As soon as they start colouring, the birds will be in like a shot. Even when netted in, they will find the one hole or gap you may have left.
- Feed deciduous fruit trees and plants now so that they have time to take up the nutrition before they go dormant.
- As a postscript to my column last week about monarch butterflies, a reader rang with the handy hint to use spring clothes pegs to suspend chrysalises which have become dislodged. You can only do this where there is sufficient stem attached to the top of the cocoon – do not peg the cocoon itself or you will damage the butterfly forming inside. She also commented that when a caterpillar in the process of metamorphosis becomes dislodged (that is the stage when the caterpillar hangs like an upside down question mark and starts to turn green) she has had success constructing small hammocks out of Chux dishcloth. They can still turn into a chrysalis and she then pegs the Chux so they subsequently hatch out successfully. There is a slight question mark over Mark’s dedication in that he has yet to enter the stage of constructing chrysalis hammocks.
Tikorangi The Jury Garden 