tomato experiment preparation
I could only reduce those insatiable mountains of foam by 20 boxes, but if you feel inspired to make a double-decker wicking bed too too dear reader, perhaps we can get something started! I have a concrete driveway beginning to be filled with poly wicking beds for my tomato experiment.
Tomorrow we’ll work our way up to lofty heights of Everest, today let’s start local!
WHY A WICKING BED?
On those exhaustingly hot weeks you just don’t want to find yourself hose in hand every night after a long day in the office with mosquitoes buzzing around your ankles.
Wicking beds have a water reservoir at the bottom so you have to water less often – about every two weeks. The water is down deep so it encourages deep roots, so stronger plants, more resilient to a bit of sunburn. They offer a more constant water source too, so in theory it should be perfect for things like tomatoes that split and carry on if their water supply is erratic.
WHY POLY BOXES?
There is so much embodied energy and money that goes into making a regular wicking bed, what with the pond liner, the brand new poly pipe, agi pipe, shadecloth, etc, it doesn’t seem the right fit for the home garden. A poly wicking bed however is entirely made of unwanted materials, so you can feel smug while you make it! Ha!
WHY DOUBLE-DECKER?
I’ve seen single poly wicking beds before, but I wanted to make them for deep rooted plants like tomatoes, so why not simply make them stackable?
INGREDIENTS & METHOD:
- LEVEL GROUND – a level surface allows water to be evenly distributed. Concrete driveways and paved areas often have a slight fall to them which could lead to water pooling down one end. Cans and pots of varying height can be used to elevate the boxes off the ground and create a more level base. A builder’s level is accurate but unnecessary, you can simply fill the container with a little water and see if evenly covers the bottom or pools at one end.
SEALED CONTAINER – no plastic pond liner or staple guns required, a broccoli box has no holes and is well insulated against temperature extremes. I simply snap the top lip off and place it on the can/pot base.
WATER DISTRIBUTION – another chance to raid the recycle bin. 7x600mL bottles with their bottoms cut off instead of the usual PVC and agi pipes. Wide mouthed ones are best because a standard hose can fit in the top, but otherwise just cut the tops off. On such a small scale, the gaps between the three bottles laid on the bottom will be enough to ensure even water throughout the reservoir. The remaining four stacked will allow you to deliver water right to the bottom of the wicking bed.
- WATER RESERVOIR – no more than 30cm deep to avoid stagnant water. Can be filled with scoria, gravel, broken terracotta pots…anything that allows big pockets of water between and can become saturated to encourage the wicking/capillary action up into the soil above. Nothing too fine as it will clog the plastic bottles. Fill with water to level out the scoria, then use a sharp stick to make 1 or 2 holes at the opposite end to the filling end. These act as overflows to prevent flooding when it rains.
SOIL SEPARATION – something to prevent the soil from getting into the resevoir, but that allows water to wick through. Hessian or old sheets can be used, they will eventually need to be replaced, but in such a small wicking bed that’s no big deal. Use shadecloth if you are looking for something more permanent. Fold the hessian up the edges of the bed so no dirt gets through and so it is easy to remove should you want to take the wicking bed apart.
NUTRIENT STORE* – high nitrogen poultry manure mixed with high carbon straw or dried leaves will make a most delightful reward for plants that grows nice deep roots. Then fill this to the brim with homemade potting mix.
- 2ND STOREY – cut the bottom out of the second broccoli box leaving a lip for it to sit on the one below. Fun fact: in a moment of despondency when my scissors broke in two I found that a half scissor works a treat at sawing through polystyrene, don’t throw them away!
PLANT POCKET/SUPPORTS – As I have mentioned before it is best to prepare any garden bed at least 2 week to a month before you plant out plants that hate transplant to avoid soil settling crushing delicate roots . That is why I made a cardboard mould the size of my plastic bottle greenhouse so I can fill the wicking bed with soil and get the companion plants established before the tomatoes are ready to plant out. It is then as simple as pulling out the mould and slipping the tomato in the hole. Add stakes/supports now to avoid disturbing roots later.
POTTING MIX – fill in the gaps with potting mix, plant some companions plants and mulch thickly. Voila, now it’s ready to plant out your tomatoes when the temperature reaches a consistent 10C+.
*TOMATO FACTS
Although tomatoes love nutrient rich soil do not spoil your tomatoes by over fertilising the soil with high nitrogen manures! They will become brattish – soft and lazy, shallow rooted plants that appear green and lush but require constant watering and attention susceptible to disease with thin skinned tomatoes prone to rot.
Additional nutrients should be delivered in the form of compost/seaweed teas ONLY once a plant has already started fruiting to extend cropping and overall yield. An even better idea is to bury poultry manure out of reach 20-30cm nearby or under your plants so their roots will access it only when they have grown deep and their fruit is ripening.
