Onions are another crop that can be tricky in the subtropics, but generally they need some patience and understanding. Most types need cold weather to form good bulbs, so for warmer climates bunching onions with their different growth habit can be a good choice. They are like permanent spring onions and they grow like massive chives, with many stems.
Growing bunching onions
Autumn is a good time to sow, to take advantage of the cooler weather. After moving here I planted mine in late Winter, which was not an ideal start, but germinated them in seed trays in the shade house to give them the coolest moistest start.
The bed I transplanted them into was also far from optimal. It’s part of the house site and made of sand over clay (a previous lawn). Consequently it dried out too easily, had low fertility, and the plants struggled through Summer.
Onions like the standard growing conditions of humus rich, fertile soil with a neutral pH, so I meanwhile prepared a plot down in my mid-levels garden, which has well dug loamy soil with plenty of compost and lime dug in, and a good water supply. I transplanted the survivors and have been amazed by how quickly they have come good. They should do well over Winter now and make for good picking after that.
Onions are fiddly to grow from seed. The seedlings are tiny and slow to progress, so they can be overtaken by weeds if you sow direct into a bed. But they are also time-consuming to plant out as tiny seedlings. Probably the best thing is to grow them on in seed trays as long as possible. They can grow in crowded conditions if they get plenty of fertiliser and water. Then the larger they are at transplant the easier they are to handle.
I am trying some bulbing onions this Winter – the ‘Lockyer’ types that have been developed for our region. I sowed early under cover in seed trays and transplanted, and although they seem to be surviving they are still very small. Fortunately they are in a bed which grew lettuce before, so I was able to get the weed burden down and lime the soil in preparation. We will see if they come good with short days and cooler weather.