French beans

OLYMPUS DIGITAL CAMERA Occasionally, garden gurus will say that “beans will grow on the smell of an empty fertiliser bag because they will fix nitrogen in the soil”. This is not true in Australia, where the soil bacteria that is necessary for these legumes to fix nitrogen does not occur naturally. Gardeners are often then disappointed to find that the lower leaves of their beans and peas have yellowed.
French or green beans (and peas) will benefit from the addition of some mature compost and a light application of complete fertiliser when preparing the planting area. Plants need more than nitrogen to be healthy and produce good crops, and compost in soil helps beans resist bean fly.
French beans do well in a sunny position with a soil pH not lower than 6. However, they may need some temporary shade during our heat wave conditions. Regular, deep watering and a 5 cm layer of mulch over the bed will help to keep them growing strongly. Bush varieties of French beans grow best when sown in a block rather than rows, and can be ready to harvest in eight to ten weeks after sowing.
For a continuous supply, sow a small quantity each month listed in the monthly planting guide for your climate.

Moving trees and shrubs

Sometimes it is necessary to move an established tree or shrub. Deciduous plants can be moved in winter or early spring, and evergreen plants in spring. This is best done in two stages if you have to move an evergreen plant, but sometimes situations arise, due to weather conditions or moving house where a shrub or tree has to be moved urgently.
This advice is for moving trees and shrubs small enough not to require the assistance of mechanical equipment.
dripline1

  1. Dig a deep trench around the plant you want to move, using a sharp spade to cut through the roots. The trench will usually have to be dug inside the drip-line of the plant, otherwise the root ball will be too large to handle. The drip-line is the area of soil directly below the outer edges of the foliage – where rain runs off the leaf canopy onto the soil. This is where the feeder roots usually lie.
  2. Water the area thoroughly, but do not apply fertiliser. Then prune back the foliage, or remove whole branches in the case of frangipani. This is necessary to compensate for a smaller root ball, so that the plant will not suffer water stress.
  3. If possible, leave evergreen plants in position for about a month, watering it regularly. This will help the plant to produce some feeder roots within the reduced root ball area.
  4. When ready to move the plant, make sure the soil is damp. Get a large piece of hessian, shadecloth or weed mat and some cord. This will help to keep the root ball intact during transplanting. A trolley, or tarpaulin or another large piece of strong fabric will help to use as a sled to drag the plant to its new planting position if the plant is too large to lift into a barrow.
  5. First dig the hole where the plant is to be positioned. Fill the hole with water. This is important for two reasons. How quickly the hole drains indicates whether drainage is good or you will need to plant the tree or shrub in a raised mound. If the surrounding soil is not damp when you transplant, the water you apply after planting will be drawn away from the root ball into the surrounding dry soil, and the plant will look stressed several days after planting.
  6. Work the spade around the trench dug previously, easing the spade further and further under the root ball until you have cut through all the roots.
  7. Place a clear mark on the north-facing side of the plant so that it will be positioned in the same orientation.
  8. Ease the fabric gently under the root ball. It will be much easier if someone helps by slowly tilting the plant to one side. Gather the fabric around the root ball and tie with cord.
  9. Carefully transfer the plant to the new hole positioning it at the same level it was planted previously. Untie the fabric and gently ease it out from under the root ball.
  10. Fill the hole with soil, adding some compost, if available. Do not trample the soil around the plant. Water thoroughly to remove any air pockets around the roots, and apply a 5 cm layer of mulch around the plant, keeping it a hand span from the trunk. Job done.

Staking a replanted tree or shrub will stabilise it until it becomes established in its new position. Gardening Australia has an excellent video on how to support plants using 3 stakes. See: 3 stake method

** Please note: Moving Eucalyptus taller than 45 cm, or other plants that have tap roots is often unsuccessful.

Cloche for seedlings update

cloche With very cold weather set to continue over much of Australia for some time, gardeners can protect young seedlings with an easy-to-make cloche. This simple structure named for the French word for ‘bell’ keeps plants warm on chilly nights and can be easily ventilated so that they don’t get too warm during the day. When the nights are milder, the structure can be easily folded and stored until it is needed again.

Instructions for making cloches can be found here: Cloche for seedlings.
** And remember to leave frost-damaged parts on shrubs until all risk of frost has passed. They may look unattractive but the burnt portions are protecting the plants from further damage.

Pruning tub plants

mandarin.jpg Citrus, dwarf fruit trees and many ornamentals grow well in large tubs. However, there comes a time when the plant is growing in the largest pot size and needs pruning to remain in the tub or pot.

To keep these plants healthy, ease the root ball out of the tub and, using a sharp knife, cut a straight line through opposite sides of the root ball – 8 cm in from the edge of the widest part of the root ball, as shown in the diagram. Trimrootball The space provided by the reduced root ball and the amount of potting mix that falls away from the root ball will allow space for enough fresh potting mix to be added to the tub. After checking that the drainage holes in the base of the tub are clear, replace the plant in the pot with fresh organic potting mix.
Trimming plants in this manner provides space in pots without damaging all the delicate feeder roots. Place a durable plant tag into the top of the fresh mix on one of the sides where it was trimmed. When you need to re-pot the plant again, make the pruning cuts at right angles to the previous cuts.

Tip pruning the foliage will compensate for the temporary loss of roots and prevent the plant becoming straggly.

Watering in drought conditions

This week, two readers have asked me about garden problems caused by lack of water. As you know, it is extremely difficult to keep gardens well-watered in drought conditions. However, as plants can only absorb the nutrients they need for healthy growth and ripeness of crops as water-soluble ions, inadequate water is the cause of a wide range of problems, including pest attack.

Bare soil in garden beds and around trees, shrubs and vines allows a lot of soil moisture to be lost to evaporation. A 5 cm layer of organic mulch over beds and around larger plants (keeping it a hand span from the trunk) will prevent water applied to the soil from being wasted. Lawns are greedy and as their roots are close to the soil surface, they take water and nutrients intended for fruit trees and favourite ornamentals. Keep lawns beyond the outer canopy of trees and cover the area under trees with mulch.

wtrbttle.jpg A method that we have found very helpful to water mulched beds is to use plastic soft drink and juice bottles to funnel water through mulch directly to the root area of susceptible plants. This is a quick and very efficient way to hand water during drought, water restrictions, heat waves or windy weather. Limp tomato seedlings will freshen up in about 10 minutes after watering by this method.
Simply cut off the base of each container, remove the lids and bury the necks of the containers about 8 cm deep near outer edge of the foliage of plants. Large shrubs may require several containers. Pour water into the container until it begins to drain slowly – an indication that you have dampened the soil in the root area.

Seedlings and pot plants are usually the first to suffer during heat waves, and you can find advice on how to revive stressed pot plants here: Pot plant stress

Corn – improving pollination

All types of corn are pollinated by breezes that blow pollen from the male flowers onto the silk threads that emerge from the top of each ear of corn. This is why it is better for home gardeners to grow corn in a block rather than a long row. Each strand of silk is connected to a separate immature seed and is covered in tiny sticky hairs that collect the pollen. If some silk strands don’t receive pollen, kernels may not form along one side of a cob, or near the top of the cob. (Female part of corn plant in photo at left.)

Male flowers form at the top of the corn plant as an upright spike and lower branches that open out like umbrella spokes. Pollen forms in small yellow ovals (anthers) that release their pollen mid morning after dew has dried from the flowers (between about 9 and 11 am). The centre spike is the first part to release its pollen. Pollen release may only last from 3 to 5 days and the released pollen is only viable for up to 24 hours. (Male flower in photo at left.)
It can help when growing small quantities of sweet corn or popcorn to pollinate it by hand, to ensure that the cobs your plants produce are full of juicy kernels. In nature, silks are rarely pollinated by the same plant.

To ensure good pollination, you need a sheet of A4 paper and a clean, dry, soft paintbrush. Fold the paper in half lengthways and open it out, then fold it in half the opposite way and open it out. This helps the paper to form a shallow well. Or, you can use a small clean shallow tray – something easy to manoeuvre between the plants. Hold the paper under a male flower and gently tap the spike and lower branches of the male flower with the handle of the paint brush. When tassels are ready to be pollinated, plenty of bright yellow pollen will fall onto the paper. Collect some of the pollen on the hairs of the paintbrush and dab it onto all sides and the centre of silk strands of other corn plants. Repeat this process over several days. Once a tassel has been pollinated, the ends of the silk strands will start to turn brown. As the cobs mature, you may have to net your corn crop as birds know when corn is perfect for eating.
Corn anthers won’t release pollen when conditions are too wet or very dry, the plants will wait until conditions are favourable. In areas of Australia that experience long periods of rain, it is best to plan your corn crop to avoid the wet season.

Ladybird larvae

Stressed plants attract pests and where you find pests you will also find beneficial insects that feed on pests. During extreme weather conditions you may notice some of these strange little creatures on various plants in your garden.

LBtransverse_lvLBcommspot_lvLBstriped_lv

LBsteelblue_lvLBmealybug_lvLBfunguseat_lv

These are not pests – they are juvenile ladybirds

Both juveniles (larvae) and adult ladybirds eat vast amounts of aphids, various types of scale and mites. One species eats fungus, including powdery mildew. The white, fluffy species eat mealy bugs. They are difficult to distinguish from the pests they devour. Australia exports this variety of ladybird to the USA to help with their mealy bug problem.

These are some images of the pupa stage, just before adult ladybirds emerge. Ladybird larvae have an attachment at the end on their abdomens that allows them to stick to a leaf surface while they pupate.

LBsteelblue_pLBfunguseat_pLBcommspot_pLBvariable_p

 

 

 

 

Lady bird larvae often seek shelter from birds in the curled leaves that citrus leaf miners produce. Remember, if you decide to use chemical or organic sprays to treat pests that you will also kill beneficial insects and their offspring. There is only one species of ladybird that is not helpful in the garden: 26 or 28 spotted ladybird.

 

For lots more information about lady birds, see: Ladybird Field Guide

Bees welcome

Beelvdr2 Although we do not use pesticides, in recent years we have noticed fewer bees in our garden. In response we have set up a hive under a white mulberry tree, and added a ‘bee garden’ in a corner of our vege patch. I’ve planted a short hedge of French Lavender (Lavandula dentata) that flowers from late autumn to mid spring, when few other flowers bloom. I’ve also added some Borage (Borago officinalis) as a treat for bees, and some Manuka shrubs (Leptospermum scoparium) to add its healing benefits to our honey.
The decline in bee numbers has become a global problem, with the United States losing  45 per cent of their bees and Europe has 13 million less bee colonies. It is a very serious problem because many of the foods we eat depend on bee pollination to produce crops or seed. If bee numbers continue to decline you can forget about having honey, the cost of manual pollination of crops would be exorbitant and many foods will become a luxury (See list below). Colony Collapse Disorder is the most puzzling aspect of this decline, where bees leave their hives and just disappear over winter.
In the past, CCD has been blamed on diseases, mites, poor nutrition, or Manuka Shrubpesticides, particularly the neurotoxic neonicotinoids. Last year, research at Harvard University found that long exposure to small amounts of two neonicotinoids (imidacloprid and clothianidin) are the likely cause of CCD. The European Union has already banned the use of three neonicotinoids, Unfortunately, Australia, that lags behind Europe in environmental issues, still allows the use of these pesticides.

TO ENCOURAGE BEES TO YOUR GARDEN:

Borage They need clean water, pollen and nectar. Keep a shallow container of clean water (e.g. birdbath) in your garden, and choose shrubs and annuals that flower in different months to provide a continuous supply of pollen and nectar. Both native bees and honey bees love our native shrubs. And, don’t use pesticides that harm bees. Read labels and Material Safety Data Sheets (MSDS) carefully before use. Your garden will benefit greatly from the presence of these tiny, hard-working creatures.

Common foods that need bees to produce, fruits, nuts, vegetables and seed
Apple, Apricot, Blueberry, Boysenberry, Cherry, All Citrus, Cranberry, Cucumber, Currants, Custard Apple, Elderberry, Feijoa, Gooseberry, Grapes, Guavas, Kiwifruit, Melons, Nectarine, Papaya, Passionfruit, Pawpaw, Peach, Pear, Persimmon, Plum, Pomegranate, Quince, Raspberry, Starfruit, Strawberry, Almond, Brazil, Cashew, Chestnut, Coconut, Hazelnut, Macadamia, Walnut, Marrows, Okra, Pumpkin, Squash, Zucchini.
Common foods that need bees to produce seed
Beetroot, Broad bean, Broccoli, Brussels sprouts, Buckwheat, Cabbages, Canola, Caraway, Carrot, Cauliflower, Celery, Chinese vegetables, Clover, Coriander, Cotton, Cowpea, Dill, Fennel, Linseed, Lucerne, Mustard, Nasturtium, Onions, Parsley, Parsnip, Pigeon pea, Radish, Rocket, Scarlet runner, Sesame, Silverbeet, Turnip.

http://www.businessinsider.com.au/harvard-study-links-pesticides-to-colony-collapse-disorder-2014-5
http://www.theguardian.com/environment/2014/jan/08/uk-food-security-honeybees

False spring

cloche Chilly days and nights after a brief period of perfect gardening weather occur every year in many parts of Australia. Australia is the only place where spring is said to start on the first day of September. Everywhere else, spring starts at the equinox when day and night are of equal length. This year, the spring equinox occurs on September 23rd.
Unfortunately, Australia’s deviation from world-wide practice tricks some gardeners into planting out seedlings while nights are still longer than days and soil is still too cold for root growth of warmth-loving plants. The problem can be solved by placing this simple cloche over beds that contain cold-sensitive seedlings. See: Cloche for seedlings.

Snake beans

Snake bean vine Snake beans are a good value crop for the vege patch where summers are hot, and French beans may struggle or be attacked by birds. They are prolific croppers over a long period and 4 plants are probably sufficient to supply a family of 4. Ours were still cropping at the beginning of June this year. A popular ingredient in Asian dishes, they can be substituted for French beans in many recipes, and blanched, young beans can be added to salads.

Snake bean pods Snake beans can grow up to half a metre or longer but tend to become a little tough if allowed to grow to this length (i.e. the beans at the bottom of the photo). They are best eaten when 30 cm or so in length while seeds are small, and they are young and tender. Pods grow fast and should be picked every day, or every second day at least, to ensure that they are harvested at their best, and to keep the vines forming new pods.
Snake beans take up very little space in the garden as they are grown on a trellis in soil that has plenty of compost and some organic complete fertiliser added, which should keep the soil pH at an ideal level (6.5–7). In late spring, when soil temperature is at least 15 degrees Celsius, sow seeds in damp soil 1 cm deep and 30 cm apart. Water to settle soil after sowing. Do not water the soil again until seed leaves appear, then water regularly to ensure healthy growth. In tropical areas where summer rainfall is heavy, sow seeds in hills to improve drainage. Seeds germinate quickly, and vines can produce pods in 60 days in very hot weather.
Snake bean ripening Greenpatch Organic Seeds has two varieties of snake bean; one with black seeds that produces pods up to 45 cm and one with brown seeds than produces thin pods to 60 cm.
Allow a couple of pods to mature until they have yellowed and lost their ‘puffiness’ (see photo). Then continue the drying process indoors. De-pod seeds when pods are crisp.