September is a great month for growing veg. The intensity of summer has lessened a little, there is still a chance of some beautiful weather, the soil is still warm and there is usually plenty of moisture for new plantings to get established. We plant a lot throughout August and this really gets going through September, almost like a second Spring. However, this month also marks the beginning of the turnaround from summer to winter crops, as many of the summer crops start to slow down in production, and winter crops begin to take over. Meanwhile in the polytunnels the tomatoes, cucumbers and beans are still going, but also towards the end of the month we will be starting to think about taking these out to make space for the winter salads and herbs.
We start a lot of sowing for winter poytunnel production from the beginning of September, with lettuce, endive, chervil, winter purslane, plus all of the brassica salad leaves like rocket, red Russian kale, watercress, landcress, mustards such as Rouge Metis, purple frills, golden frills, pizzo, wasabina and mizuna. These will all be planted around the beginning of October, once the tomatoes, beans, cucumbers and peppers have been taken out to make space. Sometimes we keep the peppers going a little longer and plant the salads around them, and although they don’t get going quite as quickly, they get their roots down, and as soon as the pepper plants are removed they put on a lot of growth. We also sow spring onions, to be planted in the tunnels, and corn salad to be planted outside. Corn salad, also known as Lambs lettuce or Mache is a delightful little salad plant, grown lots in France. It can be grown outdoors through the winter and starts producing meaningful amounts of leaves in late winter. It can be planted pretty closely together (we do it around 15cm apart just to allow a hoe to go between plants) and is really hardy.
We try to get as much green manure/cover crop sowing done as possible through September whilst there is still a bit of time for seed to germinate and start covering the ground. Most of this is sown directly over existing crops such as fennel, endive and salad leaves, hoeing the seed in lightly. Some will be sown on beds that have had crops cleared, and in this case we usually just mow down the old crops and weeds and then broadcast the green manure seed directly on this. If it is a little dry we will try to hoe or rake this seed in a little, but if there is plenty of rain this isn’t necessary. Usually at this time of year the seed mix consists of phacelia, oats, linseed, buckwheat and vetch. Some of these plants will be winter killed, whilst others will survive the winter and put on growth in early spring. The aim is to have as many living plants in the soil as possible through the winter and as much diversity within the mix, so that the soil is covered and the plants’ roots give out exudates which the microorganisms in the soil then live on and in turn make nutrients available to the plants to grow healthily.
So, there is definitely a sense of the seasons turning in September, but there is still plenty to do and the windows of opportunity are quite small as it is important to get any planting and sowing done as soon as possible so that it has time to put on growth whilst the days are still fairly long and the soil is still warm.
WHAT TO SOW THIS MONTH: Direct sown outside: turnip greens, leaf radish, red russian kale as salad leaf. Sow in trays: Now is the time to make sure you start sowing all of your overwintering salad leaves if you have a glasshouse or polytunnel, or even a sheltered spot on a patio. Leaves such as winter purslane, landcress, rocket, mustards, corn salad, endive, chervil, lettuce should be sown from the beginning of the month through to early October. Also spring onions for overwintering in a cloche or tunnel/glasshouse can be sown now
WHAT TO PLANT THIS MONTH:
OUTSIDE: salad leaves: leaf radish, winter purslane, landcress, rocket, mustards, overwintering spring onions, spinach and spring cabbage.
INSIDE: overwintering salad leaves (at the end of the month and into October), chard, coriander, chervil and parsley.
OTHER IMPORTANT TASKS THIS MONTH: Get your squash in by the end of the month and cure them either in a glasshouse, polytunnel or ideally in your house—this will make sure that the skins are hard and will last through the winter.