Preparing a spring/summer vegetable garden
The first section here covers soil preparation, watering tips and site selection. With these covered, not much can go wrong! Below this section, are 7 families of vegetables and herbs with specific guidelines for each. It is worth reading the whole article to get a good overview of what is required for a successful harvest. This will particularly help with choosing the best position for each family of vegies.
Soil, water and site selection guide
There are 3 keys to establishing a flourishing edible garden whether spring/summer or autumn/winter: soil preparation, watering and site selection
1. Soil preparation
Soil preparation is everything. Soil needs to be rich in organic matter, free draining, friable and able to hold moisture well. There are 3 main types of soil: loamy, sandy, and clay. As Banyule is built on clay, we’ll concentrate on clay soil here. The best way to lighten and add nutrients to clay soil is to add gypsum (available at your local nursery) which acts as a clay breaker and provides calcium, then dig as much compost into the clay as you can. This will add nutrients, aerate the soil, improve drainage and help retain moisture. You may even want to order some bulk Vegie Mix, (a combination of loam, cow manure and mushroom compost), to add to your soil. Vegie mix is also useful if you are building raised beds or wicking beds. Clay soils in Banyule lack boron and molybdenum so add some trace elements.
Test your soil with a pH kit. These cost about $25 and last forever. You might even want to share one with friends. The pH scale is from 1 -14 with 7 being neutral. Below 7 is acidic, above 7 alkaline. Most vegies grow in the 6 -7 range but some will grow to 8 and some as low as 5.5. Generally there is a chart in the kit with the pH range for the different vegetables. If your soil is too acidic, add lime or dolomite and if too alkaline add sulphur, and both dig and water it in. It is quicker to turn acidic soil alkaline than vice versa. Mushroom compost is alkaline so this can work as an additive but too much will turn your soil too alkaline. Follow the instructions on the additive packets carefully.
I cannot stress how much lack of water impacts development. Less than 10 mm of rain any day does not count at all. All seedlings need to be well watered at least every second day until well established and then watered deeply twice a week throughout autumn – winter – spring – summer. Water on to the soil not the leaves. This may mean placing the hose underneath cabbages or cauliflower, for example. These will not benefit from rain or overhead watering due to how dense the bed will become with leaves. Plants primarily take water up through their roots so that is where you need to get water. Watering the leaves should be avoided.
3. Site selection
Some vegies need 6 – 8 hour sun a day. This is referred to as ‘full sun’. Some need 3 – 6 hours per day. If they need afternoon sun this is referred to as partial sun, if they need morning sun this is called partial shade, The darker the leaf the less sun is needed so if you need to plant in shady areas (i.e. partial shade), plant spinach, silverbeet, rainbow chard, cress, and other dark leaved plants there plus coriander and chervil which bolt quickly in the sun. For more information, go to the article on our website: ‘How much sun do vegies need?’
Tomatoes (deadly nightshade family),
Plant September – December. Choose a site with full sun.
Dig over soil with a fork, loosening it and breaking up clods. For a 2 x 1 metre bed dig in a barrow load of compost, a bag of cow manure and 2 handfuls of blood and bone. 4 -5 handfuls of gypsum will also add calcium and break down clay. Also, add some potash, and sprinkle this around each plant again at the time of flowering. Choose the third hottest part of the garden for tomatoes, reserving the hottest for eggplant and capsicum.
Plant seeds in punnets and plant out as seedlings. Start raising seeds in June and plant out in September. Protect seedlings if frost is expected. To get a head start, plant seedlings into large pots with compost in them, and plant well established plants out when you are certain frosts are past. When planting, bury seedlings up to, and even including, the lowest leaves. This anchors them well and produces a strong root system which will deliver more water to the plant, and result in more tomatoes. Plant seedlings 1 metre apart in rows 1 metre apart. Stake seedlings and as they grow, keep tying them higher up the stake. As the plant grows, progressively remove leaves until the lowest 30 cm of the stem is clear.
Water directly, softly, onto the soil. By doing this, and through the removal of lower leaves, you will avoid soil containing septoria spores, jumping from the ground onto the lower leaves, and making their way up the plant. Always keep tomato roots moist as if they dry out, the plant will die. Water deeply several times a week.
Capsicums, chillies and eggplants (deadly nightshade family)
Plant October – December. Choose a site with full sun.
Prepare the bed as for tomatoes (above). These vegetables need long, hot summers. Germinating seeds at home, unless you have a heat mat, means that germination will be late and plants will not have time to fully mature so I recommend buying seedlings from a nursery. Seeds germinate at 28C.
Plant in the hottest spot in your garden. They need full sun and more heat than tomatoes.
Water deeply several times a week. Never let the roots dry out. As the fruit gets close to maturing, reduce the water for better quality fruit. Stake the plants and fertilise with chicken pellets every 6 weeks.
Cucumber, zucchini and pumpkins (cucurbit family)
Plant September – December. Choose a site with full sun.
Plant these as seed or seedlings on mounds of compost. Avoid nitrogen based fertilisers. Cover the mound, until the plants are well established, with wire netting to prevent birds scratching them out or small rodents eating the tender shoots. Snail bait is useful to protect seedlings from snails. Plant 3 lots of 2 seeds per mound and thin out weaker seedlings later if necessary (or transplant them). Mounds for cucumber and zucchini should be 40 cm apart and for pumpkins 80 cm apart. Rows for both should be 1 metre apart. Climbing cucumbers will need a frame. When cucumbers have 6 leaves pinch out the growing tips and they will develop lateral branches and more fruit. Add potash at flowering time for all 3 cucurbits.
Water deeply several times a week.
Plant September/October – December. Choose a site with full sun.
Dig over soil with a fork, loosening it and breaking up clods. Add compost and well rotted manure. Plant seed directly or transplant seedlings after frosts have passed. Plant in a grid pattern as corn is wind pollinated. Plant 45 cm apart in rows 50 cm apart. Plant a minimum of 5 x 5 rows. Corn requires full sun, protection from strong winds, and good drainage as it grows poorly on unimproved clay soils. For the best crop, hill up around the roots with compost.
Corn needs to be well watered which a grid layout makes difficult so dripline is recommended. Harvest close to full ripeness and before the rats are attracted to their sweetness. Rats and possums can strip a plant overnight!
Plant year round. Choose a site with partial shade.
Salad greens are tastiest and softest if grown quickly. Grow in any good soil. Keep beds and surrounds weed free to prevent transmission of viruses from weeds. They are shallow rooted and require plenty of water.
Water regularly every second day in summer. Spray with Maxicrop or Seasol every 2 weeks. Salad greens include all varieties of lettuce, corn salad, green and purple mizuna, rocket and arugula, and other exotic leafy greens.
Plant in August – December. Choose a site with partial sun.
Root vegetables need a fine tilth i.e. fine, powdery soil with all clumps broken up, and roots, sticks and stones removed so that nothing interferes with root development. Soil needs to be light, sandy and well drained containing some well decomposed compost but no manure. It needs to be dug to a depth that is deeper than the vegetable eg an 18 cm carrot needs a depth of at least 24 cm of fine tilth. (A spade’s depth is 30 cm so preparing soil to a spade’s depth is ideal).
Sow seeds direct into prepared beds at a depth of 1 – 2 cm and water well. Place a fence paling over the row and water again once the seedlings appear. The fence paling will protect the seed from being scratched out by birds but do check regularly for emerging shoots and remove the paling when that occurs. Check seed packets for depth of planting.
All will require thinning. Thin to the width plus a bit more of the fully grown vegetable. Thinnings, if small enough (2 cm), can be transplanted. In general, however, root vegetables do not transplant well and punnets should be avoided. Carrots will not germinate if the temperature is over 25C so plant these early in the season. Do not add manure as this will cause the root vegetables to split and fork.
Inadequate watering in summer will also cause splitting and forking. (Root vegetables are ideally grown in wicking beds in summer as the consistent moisture produces excellent vegetables). The main summer root vegetables are carrots, radishes, daikon and beetroot but kohlrabi and turnips grow well too.
Plant August – September. Choose a site with full sun.
Beans need well dug, well-drained soil, prepared to a depth of 30 cm. They do not require fertilising. Beans come in bush and climbing varieties, and green, yellow and purple colours. They need to be planted after frost as they burn easily. While they need full sun early in the season to develop, they do badly in full sun in midsummer and will need shade protection to continue flourishing. Climbing beans need frames for support or a teepee (eg made of bamboo sticks). If using a teepee, plant 3 seeds at the base of each pole 5 cm deep. For bush beans broadcast the seeds and cover with 5 cm of soil. Planting at this depth, prevents rodents eating the seed. Pick beans often as this will increase the crop and beans will be tender.
Water at planting and then every day during flowering and pod development. Beans need 2.5 cm water per week which is a lot.
Plant perennials year round and annuals in spring. Choose a site with full sun except for coriander and chervil. Annual herbs such as coriander and chervil should be planted in the shadiest part of the garden and well watered as they bolt easily.
Herbs grow well in poor soil and require very little water. This makes their essential oils stronger.
Written by Robin Gale-Baker