South East Queensland and Northern New South Wales have a humid subtropical climate. Vegetables grow best when the temperature (including frost), day length, rainfall and humidity suit their needs. The number and type of pests and diseases also varies with the time of year.
The humid subtropics have three seasons, which are similar to the summers of other climates: a cool-temperate summer, a Mediterranean summer and a tropical summer. The exact timing of these seasons varies from year to year, depending on whether we are in drought or other climatic factors.
Cool temperate summer is in our late autumn and winter, from late March to early August. This season has cool mornings, warm days, and is humid and wet initially, then becoming dry.
Mediterranean summer is in our spring from mid-August to late November. This season has cool mornings initially, then becoming warm, warm to hot days with low humidity and low rainfall.
Tropical summer is in our summer and early autumn, from late November to late March. This season has warm to very hot nights and days with high humidity. Rainfall can be heavy, but there are also dry periods.
Planting guide for the 3 subtropical seasons
| Plant group | Cool Temperate | Mediterranean | Tropical |
| Asteraceae | Lettuce, chicory, endive, Jerusalem Artichoke | Lettuce (non-hearting), sunflower | – |
| Alliums | Leeks, bunching onions, spring onion, garlic, onion | Bunching onion, spring onion,
garlic chives |
– |
| Brassicas | Cabbage, cauliflower, broccoli, Asian greens, kohl rabi, kale, turnip, radish, rocket, mizuna | Bok choy
Tatsoi rocket radish |
– |
| Chenopods | Beetroot, silverbeet, spinach | Beetroot,
silverbeet |
– |
| Cucurbits | – | Pumpkin, zucchini, squash, cucumber, rockmelon, water melon, choko. | Pumpkin, rockmelon, water melon, bitter melon, gourd, luffa |
| Grasses | – | – | Maize, sweet corn |
| Legumes | French beans, snow peas, peas, broad beans | Climbing beans, French beans | Snake bean, hyacinth bean,
mung bean, cow pea, soy bean, peanut, pigeon pea |
| Malvaceae | – | Rosella, hibiscus spinach | Okra, rosella, hibiscus spinach |
| Solanaceae | Potatoes tomatoes capsicum | Tomatoes, eggplant, capsicum | Cherry tomatoes, eggplant, capsicum |
| Umbelliferae | Carrots, celery coriander, parsnip, parsley, fennel | – | – |
| Various (tubers) | – | Sweet potato, yacon | Cassava, taro, yam, jicama,
sweet potato |
| Various (greens) | – | – | Amaranth,
kang kong. Brazil spinach, Ceylon Spinach, Egyptian spinach, Surinam spinach, Okinawa spinach, |
| Various (herbs) | Borage, winter tarragon | Basil, oregano, sage, thyme, mint, parsley, rosemary | Chilli, Vietnamese mint, ginger, turmeric, galangal |
Propagation
Growth of seeds into seedlings can take from 2 to 6 weeks, depending on the time of year and the time that the seeds take to germinate. So seeds need to be sown about a month, on average, before the seedlings are planted in the garden.
Propagation for the three summers can begin from:
- Cool Temperate – mid February
- Mediterranean – mid July (with greenhouse or heating)
- Tropical – early November