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05 Feb 11 Rod (Australia - sub-tropical climate)

Quite a few people had trouble this year with tomatoes. I had, what I thought was a good crop considering my back yard is badly shaded after lunchtime by big neighbours trees so I get maybe 4 -5 hours of direct sun at the equinox late Sept at very best. This is a challenge of itself, so you have to start under fluoros with the plants really close to the light to get enough light intensity. I have a big HPS & Metal Halide too, but they are expensive to run and while with practice one can get good results, I am broadly happy with a 4x4 ft fluoro to get my seedlings started at around 25 degrees (which the lights generate themselves during winter, using a very heath robinson incubator, which is just a polyester cloth cover to keep the heat in. I put in a $5 timer so, it goes off during the expensive power times and comes in at night and morning for 16 hours-ish when power is much cheaper. I managed to get a good crop this year. transplanting out Sep 1..... As Oct comes in the day length increases up to the 22 Dec where day length is at max, about 15 hours in the Sydney region. Tomatoes if well watered and well fertilized tend to grow strongly and if they are getting lots of Nitrogen and other necessary elements, will do this often to the exclusion of flowering for some time. They need (my observation using a light metre) about 10,000 lux of light for at least 4-5 hours or else they really struggle. To get this we are talking full sun for at least half the day and maybe the balance at 5,000 lux mornings and evenings so broken shade. That sounds like a typical sunny spot for some of the day, in the average suburban back yard. = mine. Commercial farmers in the flowering stage, up the Potassium levels, (it also helps with shortened day lengths) but this is to feed the tomatoes forming (more than anything else) and to keep the fertilizer regime balanced for the plants needs, using specialist leaf analysis. That is the first part, you want strong tomato plants and a good size if possible to sustain the fruit which will set, if indeterminate plants form 1-4 trusses high and maybe a lot more if you train the leaders and can string them up a bit higher or arc the stalks once the fruit has been removed and leaves trimmed away. To promote flowering what you need to do is make each plant reabsorb their own naturally occuring hormonal exudate which is given off from their own root system, (ref. ABC of NFT (Dr Allan Cooper) and which he explains deposits into the soil from the roots, under the plant during watering. I will explain the implications shortly. I grow in 10 litre trays heaped up a bit and 9 litre black 80 cent buckets, with holes in the sides, (I like everyone do not have unlimited resources, so I economise) so this helps them to flower fairly early, as I don't allow any or minimal run off, other than during rain storms, so my seeds planted in late June indoors under flouros and planted out 1 Sep, gave me lots of 150-250g tomatoes (Apollo F1) by November, but in the ground, this might be further delayed. (I ran out of tomatoes today for the first time 5th Feb) and there is 7 in our family I have been able to feed, plus the bush turkeys and possums have taken at least 1/3 of what I grew I have just layered and made 12 new tomato plants from the 2 best cherry tomatoes I grew, so expect to back in little tomatoes in a week or two. One commercial grower showed me, that once you are happy with the size of the tomato plant (in soil), stop watering it, and let it start to wilt. Outside summer this can take up to 3 or 4 days, (so I am talking serious plant stress) That will mean that it is readsorbing the hormone back from the soil, That reabsorption instructs the plant (yippee, it is time to make flowers!) Using this method and a very small pot, you can make tomatoes flower prematurely very easily. You will have to spray with organic design Dipel to kill caterpillars as stressed plants tell nature, come eat me please and the butterflies and moths will quickly oblige the call. Dipel will stop the caterpillars stone dead, and is harmless to humans, so there is negligible or no withholding period. Another tip I heard, but yet to prove is small amounts of Epsom Salts hand watered. It is a dodgy technique, but Magnesium is (if partially missing) is suddenly an important element. Dolomitic lime supplies this element, but can make the potting mix too alkali, and tomatoes seem happier acid at pH 5.5 to 6.5, & I have had good results down to 5.0 in peat, perlite and peat vermicullite blends with potting mix.....so I suggest the following to keep your pH right. Use granitic dust from your local soil supplier. 3% by volume is very good mixed into your soil plus compost or media. It will move the pH, but only very slowly over 6 weeks. It helps water holding capacity in the soil or potting mix, so if you have clay laden soil, use gypsum and it combined, as both have some real magic side effects re production and plant health, arguably by stimulating biological components in the roots and supplying other missing bits of the mystery jigsaw beyond the chemisty text books. One to two weeks seems to bring about big changes, once rock dust is applied, but its effect is only as good as the other limiting factors like light and good broad plant nutrition, and good drainage. I use a good complete fertiliser which contains balanced amounts of all fertilizer and trace elements. I mix my own fertilizer, which contains NPK plus calcium, sulpur, magnesium, manganese, iron, copper, molybdomen & zinc. That takes a bit of chemisty a spreadsheet and 5 bags of different bagged fertilizers, which I mix, so I suggest something much easier which works well also very well. Osmocote complete + Nitrophoska (both include all trace elements and both are slow release) added 50/50 @ totalling 30 grams fertilizer per 10 litres of growing media (in pots) I have found works nicely, and should have additional liquid feeds along the way. A standard not nec. premium Aus standard potting mix works well (save you some serious money) and the Osmocote has a very good wetting agent included, which helps keep everything evenly moist during the heat. The Nitrophoska has less Nitrogen so is a bit slower, but helps the flowering, but interestingly gives a nice deep bluish green to leaves, when I compared both fertilizers separately. Urea (Nitrogen source) is good for greening up) once again a suggestion by another market gardener), but you need everything else to be strongly supplied and balanced also, without any excesses. Nutricote is reportedly an excellent fertilizer. The nutrient balance is very good.....I have yet to read of a professional trial where it does not come in #1 or #2. Just make sure you get the right NPK and trace element type for or what would be suitable for vege gardening. If the fertilizer is two high in nitrogen, not so good, choose one where the K&N are close in % age terms. P is generally used in much lower levels than the other two, so don't worry to much here, so long as some is present. I grew cherry tomatoes this year with this mix and had huge amounts of fruit in Terrigal from October, growing in 4 inch deep trays. The key is small amounts of media, with as much of it open to the air as possible for root oxygen exchange (which is very critical to high productivity), but too small a container and your plant is a midget. 13 litres I have read, and pretty much proved myself, is the optimum. If you can grow in soil or a bigger pot, that is great as your tomato might be a bit or a lot bigger, but you will have to starve the plant on occasion to get it to start flowering. Currently running pot media trials, so if anyones interested email me. Interestingly my own home made mix made from a pile of grass clippings and everything that falls from palms and trees or recycled, mulched up and given a spray of water on occasion and some rock dust and fertilizer, then screened with an old tennis racket, is working as well as if not better than anything growing tomato seedlings after 2 weeks in 37 degree heat outside........seriously surprised!!! Forgive my long post, but hope this helps amateur growers just like me. Please note I am an amateur, so will continue to refine my techniques, which in 5 years might be a lot different, but so far, accoring to my limited budget this is what I have found works quite well. Good luck.

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18 May 12 Jim (Australia - temperate climate)

Am keen to further explore the issue of stressing the plant to bring on flowers. Can you stress the plant to a point of no return and have the whole plant die. Any other side effects

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17 May 12 Shaun (Australia - sub-tropical climate)

Alternatively, you could ditch all the chemical fertilisers and just dig some wilted comfrey leaves into your soil and the tomatoes will sing an organic tune all the way to your table. That's all I use and I'm still harvesting now, 8 months after the first flush of fruit appeared.

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