Why we planted 968,000 sunflowers

In late summer and into early autumn, there is nothing more beautiful than seeing fields of sunflowers with their faces glowing. They’re the best selfie buddies – and if we’d had a dollar for every person who stopped to take a photo with them, we’d probably have made ten times’ more than what we will make out of the crop itself. 

We planted almost a million sunflowers – 968,000 to be precise – over about six hectares of land. We didn’t just grow them for their good looks, or even their oil and seeds, though those are both great by-products. The reason we were first drawn to planting them was for their deep taproots, because sunflowers are as useful below the ground as they are beautiful above it.

Sunflower roots are deep and thick, which is needed to keep those heavy heads of flowers upright. This is important for lots of reasons. 

Previously, before we got here, these paddocks on the farm had been used to grow barley over and over again, so the soil had become quite heavy and compacted and, fair to say, a bit depleted.

Growing sunflowers on it instead has helped to naturally aerate the soil, thanks to those strong roots that dig down deep, penetrating and breaking up heavy clumps of soil along the way. As a result, it also encourages rainwater to infiltrate more deeply. On top of that, the best way to kill weeds is with shade; so an allelopathic plant that grows tall and shades as well is going to suppress weeds.

The plants draw carbon from the atmosphere (in the form of carbon dioxide) and convert it (via photosynthesis) into carbohydrates and sugars, which are released (via its roots) to all the wonderful microbes in the soil, in exchange for other nutrients it needs. This symbiotic relationship benefits everyone – the sunflowers, the soil microbes, and the more microbiology we have in the soil, the more it benefits us! Everything starts with the soil, and the more your soil is alive and teaming with microbes, with life, the better. 

We’re told we were the last growers in NZ to harvest their sunflowers; Carlos just harvested the seeds last week. We planted them late to avoid the possibility of frost damage (at 650-700m above sea level, we’d be the highest altitude sunflower farmers in NZ, for sure).

However we also don’t chemically spray our crops (known as desiccation) so we have to wait for them to dry out and die off naturally. And it’s a long waiting game. During that time you’re vulnerable to the birds feasting on the seeds. I must say a special thanks to “our” hawk, who I’ve named Harvey, for sitting on the fence post for days and days on end doing his best to scare off the birds (I like to believe he was guarding our sunflowers this whole time).

The seeds are harvested with a combine harvester which drives through the paddock of dead, brown sunflowers, cutting off their heads (which are filled with seeds), and then thrashes them, which separates out the seeds. The seeds are then delivered to The Good Oil, a locally owned Kiwi company who produces only NZ-grown canola and sunflower oil, to extract the oil. 

As you can imagine, sunflower seeds are naturally oily, so they don’t have to do much to them; they’re simply crushed and pressed with a huge drill to push out all the oil, then it’s poured through a filter and poured into bottles. No refining, heat or chemical treatment needed, and because it’s a locally grown and produced product, no food miles are attached to it either. Woohoo! I love that we’re keeping it local, simple and natural.

The variety we planted is a high oleic variety of sunflower, so the oil has a high level of monounsaturated fats. Sunflower oil also has a relatively high smoke point, so it’s great for cooking with. I will say though, that I prefer to use it in savoury dishes, rather than sweet – I did try putting it in a cake once and the flavour was a bit strong (often the case with cold-pressed, non-refined oils). It’s brilliant for stir-fries, pan-frying, roasting etc though. 

That paddock, once a glorious sea of golden faces, is now an ugly field of dead, brown stalks and heads on the ground. Whilst this sight isn’t as Instagrammable, everything is useful; even ugly, dead brown stalks. They’ll be “chopped and dropped”, and left to rot back down and return all the carbon back to the soil – because of their bulkiness, the amount of carbon added back is higher in sunflowers than many other plants. This will also feed the microbes again, as well as act as a mulch (ground covering), keeping in the moisture and suppressing any more weeds.