Sometimes it’s not easy to make sure your vegetables are keeping healthy and growing well when weather conditions are a little outside our usual seasonal expectations.
Cooler summer days with overcast skies, along with lots of steady rain and storms can have a significant impact on nutrient levels in soils, the soil structure, and the vegetables’ capacity to take up nutrients.
In the short term, it’s sensible to make up nutrients lost through leaching by regular applications of a complete fertiliser. But first, pay closer attention to soil health to nourish and feed the valuable ecosystem beneath our feet.
Second, manage your general garden environment more intentionally than you would under average weather conditions. Here are a few tactics.
Exposed soil is particularly prone to rain damage. Try growing a green manure crop rather than resting the soil after harvesting. I know this sounds like something you would do in a large plot or market garden, but you can easily sprinkle some seeds over the bare soil patches, rake lightly, cover with a bit of compost, mulch thinly and wait.
Suitable crops singularly or in combination include cowpeas, lupins, buckwheat oats, clover or BQ Mulch. BQ Mulch is an interesting green manure crop. It is a proprietary biofumigant mix that acts as a nursery for beneficial insects and stemming soil loss via water runoff.
Green manure crops cover bare soil with a living mulch that is then turned back into the soil. It doesn’t need to fully grow; it can just be grown for a few weeks before being turned in.
Alternatively, you could just plant more veggies right into spaces left by harvesting. Add plenty of compost and fertiliser before planting different seedlings. For example, if you have harvested the lettuce, you could follow up with beetroot.
The important point is to cover the soil with biomass and mitigate compaction and water-logging, which interferes with nutrient exchanges in the soil.
Poor root development, yellowing leaf tips, premature leaf death on plants and paler leaves in general where they should be a rich green often indicates nutrient loss.
While liquid fertiliser is an excellent way to feed nutrients to your plants, it is also important to feed the soil. Slow-release organic fertiliser in pellet form is a good way to do this.
If you have noticed fewer bees in the garden – the weather is the reason. Once the sun comes out, they will shake off their wet weather lethargy and return to work.
As a consequence of weather swings from hot to wet, you might find that pollination is less reliable this summer and your early vines, such as pumpkin and cucumber, have less viable fruit.
You can hand pollinate if this is a concern. One method is to pick a male flower, remove the petals, take the pollen-laden anther, and touch this inside the female flower (the one with the bulge that looks like a small pumpkin or cucumber at the base of the flower). That’s it. The flower is pollinated and will develop into its fruit.
As the less than stellar summer persists, the consequences will extend into autumn.
Weeds will be slow to germinate and will persist for months as dormant weed seeds, germinating intermittently and growing as the summer heat and rain alternate over the next couple of months. Ditto for fungal and bacterial diseases.
Apply pesticides when there is a few days’ break in the rainy weather. The most important factor to remember about fungal and bacterial disease spread is via water splashback from the soil to the plant – keep the soil covered.
Lastly, some planting tactics: plant your seedlings and seeds further apart than usual. The aim is to minimise plant-to-plant contact, increase air circulation, and reduce the spread of fungal diseases. The less plants are touching the less chance disease has to spread.
The veggies that don’t mind wet or damp soil and cooler summer weather include cauliflowers, broccoli, celery, silverbeet, garden pea, rocket, watercress and cabbage.
It’s also about the last chance to plant out Brussel sprout seedlings, and it is getting a bit late now to plant out a range of summer veggies such as tomatoes, corn and pumpkin. There is no way summer vegetables planted now will mature in this wet and cool season.
Bronwyn Richards and Helen Lynch run Wynlen House Artisan Village Farm and Learning Centre, a small village organic market garden in Braidwood, NSW. Since 2006 they have grown and sold fresh vegetables, eggs, preserves and garlic, and teach others to do the same.