What grows in shade
Most people who give up on growing food blame themselves. Usually it was the light. A spot that feels bright to your eyes can be sitting on two hours of direct sun, and a tomato in two hours of sun will never fruit no matter how well you treat it.
So start with the honest number. Work out how many hours of direct sun your spot gets, pick that figure below, and see what is actually on the table.
These are the crops whose minimum light requirement your spot meets. A minimum is a floor, not a promise. At the floor a crop grows slower and yields less than the same plant in full sun, and everything else still has to go right. Measured across 162 crops.
How to count your hours
Direct sun means the sun is physically on the plant, not that the area is bright. Standing in the shade of a wall on a clear day is still shade.
- Check the spot on the hour. Walk out at 9, 11, 1 and 3 and note whether the sun is landing on the spot or not. Four checks across the day is enough to get close.
- Count winter, not summer. The sun sits lower in June and July, so buildings and fences cut off more of it. A spot with six hours in January can be down to two in July. If you only measure once, measure in the cold months and you will not be disappointed later.
- Watch the whole year if you can. A deciduous tree that shades nothing in August will shade everything by December.
If that sounds like a lot of walking outside, it is. It is also the part GardenBuddy.au does for you once it knows which way your space faces.
What shade actually costs you
It is not a wall, it is a sliding scale. Leaves and stems will grow in less light than flowers, and flowers will grow in less light than fruit. That is why lettuce, rocket, spinach, silverbeet, parsley and mint keep going in a corner where a capsicum sulks. You are eating the part of the plant that costs the least energy to make.
The other half of it is speed. A crop at its minimum light will still get there, it just takes longer and gives you less. That is a fair trade for a herb you pick from all season. It is a poor trade for something you only harvest once.
Working with what you have
- Put the fruiting crops in the brightest spot. Tomatoes, capsicum, chilli, eggplant, cucumber and beans get first call on the sun. Everything else fits around them.
- Paint or use a light coloured wall behind the plants. Reflected light is real light. It will not turn two hours into six, but it helps.
- Move the pots. The advantage of growing in containers is that the garden is not fixed. Chase the sun through the seasons.
- Do not crowd shaded plants. When light is short, plants shading each other is the last thing you need. Wider spacing beats more plants.
Then let the site do the arithmetic
The filter above works off one number you estimated. Once you tell GardenBuddy.au which way your space faces, how deep it is, and what is above and beside it, it works the hours out across all twelve months, tells you which crops suit each month, and sizes the pots and their filled weight. Pick the kind of gardener you are to start, or have a look at the demo garden first, which costs nothing and is a real garden with real numbers.