Small space? Consider these aspects in setting up your garden
How do you maximise your harvest in a little space or in pots? Check out these workshop notes to learn more.© Edible Eden Design
Micro-climates affect what you can grow.
Exposed positions are great for Rosemary and Thyme; shady protected positions are good for rainforest plants like Lemon Myrtle.
- Sun - in summer your garden may need protecting from afternoon sun with shade-cloth.
- Shade inhibits certain plants such as capsicums but encourages others such as sorrel.
- Reflected light from light colored walls can contribute to plant growth.
- Retained heat from buildings can help heat loving plants such as tomatoes but hinder others such as blueberries.
- Rain shadows occur where natural rainfall is blocked by fences or buildings so plants are dependent upon you for water. You will also need to wash dust off leaves from time to time.
- Wall gardens
- Hanging baskets
Planting pots and containers
- Types – Terracotta pots and hanging baskets may need sealing or lining with black plastic to help prevent water loss. Ceramic and plastic, including self-watering pots, are good choices. Old olive oil containers or used foam fruit boxes are good recycled options.
- Size – Pots smaller than 20cm in diameter will need watering once or twice per day. Using pots that are much bigger than the original plant is called ‘over-potting’ - a loose and unstable root ball will eventuate, which will usually collapse when you repot the plant in 2-3 years.
- Drainage – All pots need holes for drainage. Use ‘pot feet’ under pots or inside saucers to allow pots to drain properly.
Potting mix and additives
There is no such thing as a good quality cheap potting mix! Use a good quality potting mix if you want good growth.
- Fertilisers –Instead of slow release chemical fertiliser balls use slow release pelletized manures. Liquid seaweed or fish emulsion fertilisers provide easily absorbed nutrients.
- Water-saving – adding worm castings or homemade compost in your pots will increase its ability to hold water.
- Mulches – Straw mulch (eg. pea straw) is best for vegetables and herbs as it breaks down and adds organic matter.
Basic rules for potted plants
- Plants generally need repotting after 2-3 years.
- Water well before repotting to ensure evenly wetted roots and after repotting to settle potting mix around roots.
- Trim roots when re-potting if pot-bound by cutting off 12-25mm from all over root ball.
- Plant to the correct soil level with the top of the root ball at the surface of the potting mix.
- Don’t use rubble in the base of pots! (An exception is that charcoal can be added to the base of tall pots).
- Allow larger more established plants to (just) dry out between watering. Small plants and seedlings should never be allowed to dry out.
- Let water drain through pots thoroughly at each watering to avoid a build-up of fertilizer salts in potting mix.
- ‘First aid’ for a potted plant that has been allowed to dry out to the point of drooping: Plunge whole pot into a bucket with diluted liquid soil wetter to re-hydrate. A home-made alternative is to use a small squirt of mild dish detergent in a 10 litre bucket of water.
Pests and problems
- Isolated environment – Balconies are not part of a larger garden ecosystem, so probably have no predator insects. Plants are therefore reliant on you and harmful insects can quickly devastate plants.
- Avoid sprays where possible, but if spraying use organic preparations. When spraying, consider what’s in close proximity.
- Aphids can be sprayed off with water, soap spray or garlic spray.
- Mealy bug, scale and 2-spotted mite can be treated with Eco-oil or a mild soap based spray.
- Caterpillars can be hand-picked off, as can their small green eggs before they hatch.
- Sooty mould can be wiped off leaves with soapy water then rinsed off.
- Powdery mildew can be prevented with milk diluted 1 in 10 sprayed on leaves. (Remove any already affected leaves first).
Big Harvest – which varieties give the best harvest in a small space?
Fruit varieties suitable for growing on balconies in pots:
Apples – need two varieties for cross-pollination. Check on labels or with nursery staff
- Dwarf ‘Pink Lady’ pollinates Dwarf ‘Gala’
- Dwarf ‘Golden Delicious’ pollinates Dwarf ‘Jonathon’
- Dwarf ‘Bramley’s Seedling’ pollinates Dwarf ‘Cox’s Orange Pippin’
- Ballerina apples are columnar shaped trees – choose from ‘Bolero’, ‘Charlotte’, ‘Flamenco’,
- ‘Polka’, ‘Waltz’, remembering to check which will cross-pollinate
- Ballerina crabapple is the columnar crabapple variety named ‘Maypole’
Citrus – (self-pollinating)
- ‘Lots-a-lemons’ is a dwarf rounded shrub form of ‘Meyer’ lemon
- ‘Tahitian’ Lime – can use leaves in cooking to replace Kaffir lime
- Kaffir lime is small enough to grow in pots on regular rootstock, not dwarf.
- ‘Lemonade’ is available on dwarf rootstock
- Citrus ‘Splitzer’ has two varieties on one tree – lemon/orange, lemon/lime, Kaffir lime/Tahitian Lime, mandarin/orange
- Cumquats are suitable for pot culture.
- Many other citrus varieties are available on dwarf rootstock
Stone fruit suitable for pots
- Dwarf nectarine – small shrub, little or no pruning, spring blossom, normal sized fruit
- Dwarf peach – small shrub, little or no pruning, spring blossom, normal sized fruit
Espaliers – ornamental and efficient way to grow fruit, easy to pick and protect, needs a permanent structure to be trained on.
- Dwarf apples - need two varieties for cross pollination
- Dwarf pears – need two varieties for cross pollination.
- Feijoas can be used as a blue-green leafy espalier screen.
- Strawberry and Yellow Cherry Guavas make lush evergreen espaliers or living screens
Hedges – plant a row of pots to make a balcony windbreak or privacy screen
- Strawberry guava (Psidium cattleyanum) prolific tart red fruits in Autumn, lush evergreen hedge to 1.2 – 2m high.
- Yellow cherry guava – (Psidium littorale var. littorale) – sweet yellow fruits in autumn, lush evergreen hedge to 1.2 – 2m high.
- Blueberries – Small deciduous hedge with beautiful autumn leaf colour, 50cm – 1m high. Fruits in summer, must have adequate water and prefers protection from afternoon sun.
- Chilean guava (Myrtus ugni) fruits in late Summer, needs adequate moisture, short evergreen hedge to 30-50cm high
- Feijoa – fruits in Autumn, tolerant of exposure to wind and sun, can be kept to 1.5- 2m high
- Native mint bush (Prostanthera rotundifolia) evergreen hedge to 1- 1.5m high
Vines and berries
- Grapes must be grown in a large deep pot.
- Raspberries can be grown in large deep pots with adequate moisture.
- Alpine strawberry will fruit well when well fed and watered
- Strawberry ‘Cambridge Rival’ – small strawberry with superb taste
- Strawberry ‘Pink’ – decorative and edible, with pink flowers
- Strawberry ‘Temptation’ - produces into autumn
Standards - Fruits and Herbs
- Kaffir or Tahitian Lime
- Native Citrus
- Lemon Myrtle (Backhousia citriodora)
- Bay Tree
Vegetables suitable for small spaces
Salad herbs and vegetables – Autumn, winter, spring in full sun, summer in shade…
- Baby Cos, Curly leaf, Coral lettuce
- Oak leaf lettuce – green or purple
- Rocket – spicy leaves and edible flowers
- French sorrel - use to add lemony zing to salads, or make sorrel and potato soup
- Tatsoi – salad leaf
- Mizuna – salad leaf
- Mustards – Leaves spice up a salad or can be used in stir-fries where they lose their spiciness
- Red-ribbed chicory – adds colour to salads
- Red dock – young leaves give colour to salads, old leaves can be added to cooked greens
- Land cress
- Nasturtium – use peppery leaves and flowers in salads and flower buds can be pickled in vinegar and used instead of capers
- Edible Flowers – violas, calendulas, caraway flowers, chive flowers
Repeat or long harvest vegetables including ‘cut and come again’
- Bok choy – harvest individual leaves from outside in
- Sprouting broccoli
- Silver beet, 5-coloured chard
- Perpetual spinach
- Mizuna – Use leaves in salads or add to clear soups just before serving
- Chicory – Bitter winter greens to stir fry with garlic and olive oil Italian style
- Flat-leaf parsley – tabbouleh, mixed salad, can also use in soups, risottos, omelettes, pasta sauces, and casserole
- ‘Tuscan’ Kale – cook leaves like cabbage, and use young leaves in salads – varieties – Tuscan, Russian Red, etc
- Perennial spinach – eat young leaves raw, cook older leaves
- Spring onions – Long-lasting onions, can use in place of onion in any recipe
Summer crops (Plant in spring/early summer) – Small or repeat varieties
- Tomato ‘Tumbler’ – suitable for hanging baskets too – trailing plant
- Tomato ‘Patio’ – for medium sized pots
- Tomato ‘Nellie Kellie’ – suitable for hanging baskets or small pots
- Eggplant – Lebanese ripens quickly, prolific and long harvest
- Cucumber ‘Spacemaster’ – or use a bush cucumber eg ‘Bush Bonanza’
- Pumpkin ‘Delicata’ - bush pumpkin
- Chilli – choose according to your preference for heat!!
- Capsicum – ‘Mini Mama’ or ‘Mini Sweet’(Diggers)
Winter to early spring crops (Plant in late summer/autumn) – Small or repeat varieties
- Bok choy, Pak choy – can be cut off leaving 2-3 leaves to re-grow at least once
- Beetroot – for pots try a variety such as ‘Mini gourmet’
- Broad beans – eg Coles dwarf
- Broccoli – Calabrese sprouting gives a repeat harvest from side shoots
- Cabbage – Diggers ‘Mini’
- Carrots – choose a round variety eg. ‘Mini Round’
- Cauliflower – Diggers ‘Mini’
- Radish – plant any time. Small varieties eg. ‘Round Red’
- Snow peas eg. Sugar snap dwarf. Trailing plant, no support
- Mizuna – leaves can be continuously harvested over time
- Asian greens –prefer the cooler weather
A word about herbs…
- Most herbs grow better in pots – due to the warmer soil and good drainage
- Herbs such as basil enjoys the extra warmth of a pot
- Peppermint, spearmint, mint, lemon balm are best grown separately as they are very vigorous
- Remember to divide and repot running herbs such as oregano and mints every two years
- Thymes grow well in pots in a sunny spot – try lemon thyme, orange thyme, etc
Grow your own herbal tea!
- Lemon-scented myrtle
- Lemon verbena (leaves will be smaller than if grown in the ground but just as fragrant)
- Lemon balm
- Pineapple sage
- Microgreens are eaten when larger than sprouts & seedlings
- Sow seeds thickly in a shallow pot or dish with good drainage
- Cover with a thin layer of soil and keep moist
- Harvest by cutting above soil level
- Use in salads, stir-fries or add to soups before serving
Also try growing…
- Snow peas
Remember – Around 30% of our carbon footprint is generated by the food we eat, so anything you can grow yourself makes a difference!
Salad greens and herbs have a large carbon footprint so are your first choices to help the environment. They also lose their nutrients quickly after picking, so are much healthier grown at home.
Happy produce gardening!
© Edible Eden Design