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This is a little message to all our Seedsavers members, please take some photos of your patch of earth and share them with us. Or tell us about what you plan to plant in autumn. Tell us you are still there and have not given up after our summer heat. Lets share our successes and failures, on the blog

Tomato Troubles

Tomatoes are usually one of the most rewarding vegetable to grow in your backyard, however their fussy tendencies and willingness to up and die at their peak makes me wonder why Ibother. This year I thought I had it right; I rotate the crops accordingly & planted a cover crop of mustard and legumes, added compost. Then at planting I added calcium aged manure and aspirin deep in the planting hole, a method to add disease resistance. They flourished beautiful strong healthy plants, which I watered and fed fortnightly with fish emulsion, seaweed concentrate and aspirin dissolved in water. I also covered their pretty little head with shade cloth to protect them from the suns rays.

So what went wrong? I figured the heatwave was just too much for them and so decided to pull them out. The real answer was glaringly obvious, staring right at me in a knobbly ugly knot of roots. My tomato plants were affected by Tomato root knot nematodes.

Root-knot nematodes (Meloidogyne spp.) are minute, worm-like animals which are very common in soil. They have a wide host range, causing problems in many annual and perennial crops. Tomatoes are among the most seriously affected, with the nematodes causing problems in all growing area Root-knot nematodes do not produce any specific above-ground symptoms. Affected plants have an unhealthy appearance and often show symptoms of stunting, wilting or yellowing.

Symptoms are particularly severe when plants are infected soon after planting. More commonly, however, nematode populations do not build up until late in the season and plants grow normally until they reach maturity. They then begin to wilt and die back with flowering, fruit set and fruit development being reduced.Below ground, the symptoms caused by root-knot nematodes are quite distinctive. Lumps or galls, ranging in size from 1 to 10 mm in diameter, develop all over the roots. In severe infestations, heavily galled roots may rot away, leaving a poor root system with a few large galls.

The common species of root-knot nematodes all have a wide host range, and most plants are able to host at least one species. Many important fruit, vegetable and ornamental crops are good hosts of these nematodes, they include:
banana, cucurbits, grape, carnation, passionfruit, nectarine, capsicum beans, kiwi fruit, chrysanthemum, pineapple, tomato, carrot, eggplant, strawberry, rose, peach, celery, ginger, lettuce, papaw, pumpkin.

Nematode management
Crop rotation
Root-knot problems increase, and control becomes more difficult, when tomatoes or other susceptible crops are grown without rotation. Crop rotation will not eliminate infestations because root-knot nematodes can remain in the soil as eggs for at least a year between host crops, and most species can feed on a wide range of weeds.
However, rotation can significantly reduce losses when a field is again planted to a susceptible crop. Winter cereals are useful because they are generally poor hosts and little nematode reproduction occurs during the cold winter months. It is more difficult to find summer crops with good resistance to root-knot nematode but sorghum x Sudan grass hybrids (particularly cv. Jumbo) are useful against most populations of the nematode.

Fallow and cultivation
Repeated cultivation kills nematodes in the upper soil layers by exposing them to mechanical abrasion and the heating and drying action of the sun. If the field is maintained weed-free, nematodes also die of starvation. In warm, moist soils in Queensland, a 4 to 6 month fallow may reduce root-knot nematode populations by more that 95%. Longer periods of fallow are not normally economically feasible, and risk of soil erosion is increased.

Sanitation
Nematode populations have the capacity to increase rapidly, so to prevent further multiplication, plants should be ploughed out as soon as the crop is harvested. At this time, most of the nematode population is in the roots rather than in the soil, so if these roots are removed from the field and destroyed (e.g. by burning), there is an immediate and substantial reduction in the nematode population.

Organic matter and numbers of root-knot nematodes in tomato
Soil organic matter is known to be detrimental to nematodes. Laboratory and glasshouse experiments examined the inhibition effects of molasses on root-knot nematodes. Molasses was found to inhibit both egg hatching and juvenile nematode motility. This result indicates that the inhibition is probably due to antagonism towards nematodes by micro-organisms.
The suppressive effects of sawdust+urea, filter press, molasses, a green manure cover crop and a nematicide were compared in the field. The plots were maintained for three successive tomato crops to determine the long-term effects of such treatments. The effects of the organic soil amendments on root galling and nematode populations are shown in Table 3.

Timetable for decision-making on nematode management in tomatoes
Approx. time before planting date (months)

-12 months
Remove plants without shaking the soil from the roots. Destroy nematode-infested root systems Infested plants must be burned, or sealed in plastic bags and disposed of in the garbage.

-8 Months
Plough out crop immediately after harvest.
Maintain a weed-free fallow until a cover crop is planted.
Plant a cover crop that is not susceptible to root-knot nematodes, e.g. winter cereals or forage sorghum, mustard,

-2 Months
Collect soil samples and either: do a bioassay; or test soil for nematodes.

0 Months
If the results of nematode analyses or bioassays, or the previous occurrence of nematode problems, suggest nematodes are likely to cause damage, either:
plant a nematode-resistant variety; or
apply a pre-plant nematicide. Where severe infestations occur, rest soil from growing host plants for three years. Control weeds assiduously.

Nemodode Information supplied by Tony Pattison, Department of Primary Industries and Fisheries, Queensland.

Saving Tomato Seed

Tomatoes are self pollinating, making them an easy choice for saving seeds. The earliest and more attractive plants of a variety should be marked, staked and inspected during the growing season for desease and immunity from pest attacks. the best fruit of the lower three bunches/hand of each plant is best for seed.
Allow the fruit to ripen just beyond the eating stage. cut them open, squeeze out the jelly and seeds. if it is a dry variety such as Italian plums ect you may have to ad a tiny amunt of water.


Label the container and leave in a warm spot for two-three days, undistirbed. a foamy scum will form on top and it will look as though something has gone horribly. Don’t worry. This is a beneficial fermentation process that kills off several diseases that can affect tomato plants, but the mould can cause premature germination of the seed, if it is left too long

As soon as the foam forms, scoop it off the top and fill the container will clean water. Viable seed sinks to the bottom of the jar. Carefully pour off loose jelly floating at the top of the jar, then pour the jar contents into a sieveadd water . Wash and rub until clean. The jelly around the seeds will have been washed off. Spread them out in a single layer, somewhere dry and out of the sun.

Letting them dry on a plate or large dish stops them from sticking to the surface and then after a few hours of drying you can rub them between your palms to stop them sticking together.


Put the seeds in a labelled envelope and hang to dry for two weeks. It is imperitive that you label at all stages, especially if you are saving more than one variety of tomato.

Kindly reproduced from Seed savers handbook

Monthy Natter - Feb

Our first meeting for 2009 went well, small but nevertheless productive.

As I mentioned in our group email the calender for 2009 was discussed, some good ideas resulted and I will post it for comments sometime this week. If anyone would like to host a meeting please speak up.

Tomatoes... again small but productive. Derek & I discussed a couple of ways to save tomato seed and found his method suggested of letting the seeds ferment in situ to be very logical, after all that is how nature intended. That is; to pick best bunch or branch of tomato/s and hang them in dry sunny place so fermentation occurs withing the tomato. I would be very interested to hear if any one else has tried this method, and their results. This is opposed to fermenting seeds in dish, as below. As for our varieties to show off. Derek had a nice yellow tiger, which he was a little disappointed in size, but it still made an excellent salad tomato, and I had the Tatura dwarf varieties purchased earlier from Eden seeds. So far they have been excellent, in taste, vigour, disease resistance, however the heat knocked them and they haven't really bounced back.

We also compared other summer successes...bunching onions were a winner for me, neither of us had much luck with climbing french beans in the heat, Derek once again will have a lovely crop of muffet beans, dried for winter soups and stews. My Romanesque zucchini is a real winner, no sign of mildew at all and doing exceptionally well growing in a pot. The flowers for stuffing much superior over black & gold varieties. Derek also passed on a great bounty of seeds,, fresh parsnip, lots of coriander, kale.

On writing this Kaye will be performing with the community choir at the SheppARTon festival this evening, so I wish her well and hope to see you all soon.

Carley