So, how do you know what to sow, when and where? It is very helpful to have a local gardening guide, and here in New Zealand, www.gardengrow.co.nz is very, very useful. This website lets your choose your gardening region, then shows you what to plant this month and next, with details of how best to plant it, plus all plant names are linked to a page with more detailed growing and harvesting information. You can also subscribe to the email list, and get a weekly or monthly list of what to plant directly into your inbox. I find this an excellent tool.
On top of that, it pays to use local knowledge, as each area has it's own microclimate. So talk to your neighbours and those in your area who garden, and ask them when they plant specific things. In time, you will build up your own local seasonal knowledge. Keeping a gardening diary is an invaluable tool in achieving this - I'll post another article soon about my own gardening diary, what is in it, and why.
One more consideration - gardening by the moon calendars can be very useful too. Many people are certain the moon makes a big difference to plant growth, and my own experiments this year have shown that to be true. If nothing else, it is helpful to have a plan as to when in the month to concentrate on planting above-ground crops, when to plant root-crops, and when to concentrate on prepping, pruning and harvesting. All these things need timely attention, and something that helps you plan a monthly cycle can be a useful tool. I like NZ Gardener Magazine's downloadable moon-calendar. This is reusable one because each month you just turn the disc to line up with the new moon date for the month, and it tells you everything else. I keep a copy in the front of my gardening diary. You can find it here: http://nzgardener.co.nz/moon-calendar/