Seeds lose their vigour over time and, they can deteriorate more quickly than they should if storage temperatures or moisture levels have been unsuitable. If a batch of seed has not germinated well I do a germination test on some of the seed to see if it’s worthwhile trying another crop.
All I need for this is a wide mouthed screw-top jar, a saucer, and some cotton wool.
I place the cotton wool in the centre of the saucer, and add enough water to wet it thoroughly – but not enough to allow it to float in the water. Seeds absorb a lot of water during germination, and inadequate moisture alone can cause germination failure. I then check that the cotton wool is covered by the inverted jar.
Then I sprinkle a sample of the seed from the suspect batch onto the cotton wool. If the seeds are large, such as corn or cucurbit seed, I use the blunt end of a pencil to press the seed firmly onto the surface of the cotton wool, so that they have good access to moisture. This is unnecessary with small seed.
When I place the jar over the cotton wool I have a miniature glasshouse. Most seeds require dark for germination; and I place the mini glasshouse in a dark cupboard that is not opened frequently. I check the jar every three days for signs of activity. To test if the cotton wool is still moist, I lift the jar and check that the cotton wool is still moist. If necessary, I add a few drops before replacing the jar.
Some vegetables such as most lettuces, cape gooseberry, seakale, shiso and tomatillo, and some herbs and gazanias require light for good germination. For these seeds the jar can be kept in a well-lit room out of direct sunlight. Seed packets will indicate the best conditions for that species’ germination.
Most common varieties of vegetable seeds will show activity in a fortnight or so, but some, including capsicum, carrot, celery, eggplant and parsley can require a month for germination to occur.
If the majority of the seeds show signs of germination, the problem is more likely to be the growing mixture, lack of adequate moisture, or unsuitable soil or growing mix temperatures. If germination is poor or the seeds don’t germinate at all, and the seed was purchased recently, the supplier should be contacted to replace the seed.
To reduce problems with seeds, packets should be kept in a cool stable environment where they are protected from moisture and pests. A metal biscuit tin makes a suitable storage container if the tin is kept in a cupboard in the centre of the house where temperature fluctuations are minimal.
Seed sales for edible plants have boomed as many house-bound people have adopted the ‘green therapy’ of gardening. Organic gardening has long been respected for providing healthy outdoor exercise and mental health benefits while providing healthy, pesticide-free produce for your family.
My book Easy Organic Gardening and Moon Planting has been helping gardeners get the best from their gardening efforts since 2006. It provides practical advice on what to grow when in the perpetual monthly diary, and how to get good results in both your vegetable patch and ornamental parts of your garden. It can be used with, or without, moon planting. There are also sections on compost making, worm farming, drought-proofing your garden, and much more. See reviews: My book
Easy Organic Gardening and Moon Planting is available as both a paperback and e-book, and can be ordered on-line, so you don’t have to leave home to find it. Happy gardening, everyone.
This lovely climbing rose is a popular addition to many gardens. The Banksia Rose, (Rosa banksiae) or Lady Banks Rose, originated in China, and is named after the wife of famous botanist Sir Joseph Banks.
An evergreen rose with few, if any, thorns, it is a dense climber to about 6 metres – perfect for covering a fence or pergola. Masses of creamy yellow or white flowers are produced on long canes from spring onwards. The flowers have a delicate fragrance, some say reminiscent of violets.
This vigorous rose needs a well-drained soil in full sun or part shade where it won’t crowd out other plants. First fill the planting 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 rose 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. The addition of compost to the planting hole, and a 5 cm layer of organic mulch to the soil surface, is very beneficial. Keep the mulch one hand width from the stem.
It is a hardy plant but it should be watered weekly for the first couple of months after planting if weather is dry. Then, only water when the top centimetre of soil is dry.
Climbing roses are pruned after flowering. Banksia roses are usually pruned by late summer when the main flowering flush has finished. As these roses flower on last season’s wood, just remove any damaged canes, and shorten the rest of the canes by one third. Hard pruning results in no flowers next spring. Prune new roses during First Quarter phase when sap flow is higher and growth response will be faster.
Galls or stem swellings on citrus trees need to be removed by pruning by the end of August, as very tiny black wasps emerge from the galls in September and October ready to lay a new batch of eggs in citrus stems. Because these wasps are poor fliers, they tend to reproduce on the same tree unless blown by wind to a new host.
Unlike many other wasps that assist pollination or are pest predators, the citrus gall wasp is a true pest. Eggs are laid in young stems of citrus trees, particularly lemon and grapefruit varieties, and the native finger lime. The larvae remain within the stem, stimulating the growth of cells, and causing a gall or swelling to form on the infested stem by early summer. Trees that are repeatedly attacked will become weaker and produce less fruit.
Originally, only coastal gardens of New South Wales and Queensland were affected, however, this wasp is spreading to other areas of Australia.
Do not add galls to the compost heap. Burn them, or dispose of them in a sealed plastic bag. It is very likely that the gall in the photo missed last year’s pruning because it is unusual for galls to reach that size in one season. As you can see, the tree in the photo is also affected by scale, and it is more common for citrus gall wasp to attack stressed trees. After pruning, water the tree thoroughly, and feed it with a complete organic fertiliser and as much compost as you can spare. A drink of seaweed extract tea will help it to resist further pest and disease attack.
Not only do organic ‘Midnight Purple’ potatoes add interest to a potato salad, purple potatoes are very good for you. Like richly-coloured berries, purple potatoes are full of anthocyanin pigment, an excellent anti-oxidant that we are told is important in maintaining good health. Purple potatoes also contain chlorogenic acid, which is beneficial to the health of our blood vessels and, of course, important fibre. There is a range of purple potatoes now available, with varying degrees of colouring. I particularly like the Midnight Purple ones as they are an intense purple all the way through.
If you would like to grow your own, Green Harvest have a good selection of purple potatoes, see: Green Harvest potatoes.
Advice on how to grow potatoes can be found here.
Other ways to grow potatoes.
Happy St Patrick’s Day.
Just a brief post to let moon planters know that from today, 17th March 2018, the current moon phase can be found by clicking on that link in the menu bar on the Aussie Organic Gardening blog.
For those not familiar with moon planting, see: All about traditional moon planting.
This ugly little creature is the larva of the leaf-eating ladybird. Stressed plants in prolonged hot, dry conditions attract these pests. The larvae become almost black as they reach pupa stage. Both adults and larvae of leaf-eating ladybirds are particularly fond of the Solanum family (tomato, potato, eggplant) and the melon or squash family where they do a lot of damage to leaves.
The adult leaf-eating ladybird has 26 or 28 spots in rows across its wing covers. They are slow moving and drop to the ground when disturbed. In summer, if you see the adults on leaves in your garden, be sure to look under the leaves for their eggs. Remove small leaves containing eggs and, on large leaves, use a knife to scrape the eggs into a container. As I dislike spraying my garden, I just squash the adults and larva with a gloved hand.
Unfortunately, the damage done by these ladybirds and their offspring have resulted in many gardeners spraying other species of ladybirds that are voracious pest predators. Both adults and larvae consume a considerable quantity of pests such as aphids, scale and mites, and one type of ladybird feeds on fungus. Peter Chew and his family have an excellent website, Brisbane Insects and Spiders, where gardeners can easily identify which creatures are beneficial to their gardens and which are pests, and includes a Ladybird Field Guide.
The photo below shows both larva and pupa stages of the 28-spotted ladybird.
A common problem affecting otherwise healthy tomato and capsicum plants during heat waves is blossom end rot, where partly formed fruit develops a dark, sunken patch furthest from the stem.
This is caused by calcium deficiency, and is not a disease. Like us, plants need a good supply of calcium to form a strong structure. Hot and very windy days increase transpiration (water loss) from plants in the same way we perspire to keep cool, and calcium can only be absorbed by plants as water-soluble, electrically-charged ions. This problem can also affect zucchini, pumpkin and melon plants.
During heat waves, daily watering rarely solves the problem. A deep watering a couple of times a week is more beneficial. If soil around plants is mulched to keep roots cooler and reduce water loss, an efficient way to water quickly is to place juice or soft drink bottles, neck down, beside plants. See: Watering in drought conditions
Other causes of blossom end rot are:
• Erratic watering
• Soil is too acidic (soil pH less than 6)
• Poor fertilising routine
• Overuse of fertilisers high in nitrogen or potassium, including some seaweed fertilisers
• Rarely, in very alkaline soil where calcium becomes insoluble.
There is nothing like the taste of vine-ripened tomatoes, and this is how my neighbour, Cheryl, keeps her tomatoes cropping through winter on the Mid-North Coast of NSW. The tomato plants self-seeded in the rose garden in front of her north-facing verandah and, as they grew, she trailed the foliage across the verandah surface. The plants get plenty of sun during the day and the verandah roof keeps the plants warmer at night and protects them from frost. This clever idea has worked very well and Cheryl has so many tomatoes, she has been giving them away.
Tomatoes can also do well during the colder months in pots on a protected north-facing verandah, as the potting mix in black plastic pots stays warmer than soil in garden beds. Fruiting on tomatoes depends on warm air and tomatoes do not need bees for pollination. Don’t forget to water the plants regularly, and give them a light application of complete organic fertiliser as flowers start to form, to ensure a sweet-tasting crop.