Do my tomato plants look developmentally delayed to you?
A lot of the fruiting crops in my garden seem a bit delayed this year. This is probably due to a cool, wet spring, but in the case of my tomato plants I have become a bit anxious about lack of growth and especially lack of flowering. No flowers = no fruit = no tomatoes to bottle two months from now. So figuring that extra plant food won't go amiss even if it is just a seasonal delay, and is essential if it is not, I have started feeding the tomatoes with liquid feeds of various kinds.
I brew these in a container which the Christchurch city council thoughtfully provided. I was expected to put my organic kitchen waste into this little green-lidded wheelie bin. Then the council workers were to remove it once a fortnight and transport it 50km to the nearest council composting facility. There big machines would mix it with everyone else's waste, turn it into compost and bag it, so it could be sold back to me! (Possibly contaminated with weedkillers from the lawn clippings which people also put in these bins, which are powerful enough to kill young tomato plants even when at minute levels.)
While this system is less stupid than dumping organic waste mixed with non-organic waste, which used to happen until quite recently, it is still far from an optimally sustainable system, relying as it does on huge amounts of fossil fuel energy to lug the stuff around, turn it into compost and sell it. How much cheaper, easier and more sustainable it would be for the council to provide every household with a compost tumbler, compost bins, or similar, so that they can make their own compost on site at no energy cost, and with no further greenhouse gas emissions.
I have of course continued to do this with my organic waste, so I continue to have free compost, and I have realised that the wheelie bin provided for organic waste is a perfect brewing vessel for liquid plant foods. It is capacious and sturdy, and I can easily wheel it to where I want to fill it, or use it. My last brew was 'seaweed tea', which went on the tomatoes last week. This week I am brewing 'comfrey tea', as comfrey is rich in the potassium which tomatoes need to grow well.
Comfrey leaves ready to go into the wheelie bin for brewing.
My method is not very scientific – I just stuff the comfrey leaves into the bin, add water to cover, push them down, and leave the brew to get smelly, which takes 10-14 days. At that point it can be applied to the plants. Apply it to the root area only if feeding tomatoes, and make sure the ground is already damp beforehand. The sludgy used comfrey leaves make a good mulch.
If this method is a little too free and easy for you, then according to p. 51 of Richard Llewellyn Hudson's book Organic Gardening in New Zealand (an oldie but a goodie) the proper ratio of comfrey leaves to water to make a strong comfrey liquid manure is 6-7kg leaves to 100 litres of water. This should be left to ferment for a month, and the resulting liquid diluted to half strength with water before being applied to plants.
Organic liquid feeds can also be made with animal manure, weeds and compost – see this helpful advice from the gardeners at Mas du Diable for more information.