Explainers

How to grow rocket

A vegetable patch without rocket lacks a great staple, according to Mat Pember. The perennial performer is a leaf for all seasons.

Peaches with burrata, prosciutto crudo and rocket
We all require a few basic needs to make us happy. I consider these to be a job, a home and Radiohead's 1997 album, OK Computer - without any one of them life would quickly become hollow. The same can be said about the garden. There are some needs so basic that without them the garden begins to feel empty. And I'm not talking about sun, soil and water, which are of course givens, but rather a vegetable-patch staple: rocket.
Perhaps it's my Italian heritage, but a vegetable patch without rocket is just not a vegetable patch. Rocket is the evergreen, ever-ready leaf that grows any time of the year in almost all regions of our country. The most challenging thing about this perennial performer is that it can be difficult to keep up with its production. A rocket plant loaded with leaves will bolt to seed when it's not picked regularly.
If you're growing rocket from seed, it's best to propagate it in a mini greenhouse so the early weeks are nicely incubated. Hot midsummer temperatures will play havoc with any propagation, but a greenhouse recycles moisture. When the soil is kept damp and out of strong direct sunlight, germination occurs quickly - usually within a week.
After a few weeks of regular watering, ensuring the soil doesn't dry out but isn't waterlogged either, you'll notice quick growth; the rocket is now ready to move to a permanent patch. The best time for planting, as a rule, tends to be the time and day humans least enjoy: the morning of an overcast day. While it may be hard to summon the enthusiasm for gardening, it's ideal for planting and your rocket seedlings will be appreciative.
When you're transplanting them into a pot, use a good organic potting mix that's free-draining and loaded with natural fertilisers. For planting in the patch, integrate compost into the soil to ensure it has adequate reserves of nitrogen, which is necessary for healthy leaf growth. As with any edible plant, the more sunlight you provide the better rocket will perform.
Rocket doesn't mind growing in close quarters, but the plants prefer to be spaced around 10 centimetres apart. If you become inundated with seedlings, cull them once they're large enough to use in the kitchen - young germinated seeds make great micro-greens.
Given the time of the year, mulching, watering and harvesting are absolute prerequisites for maintaining healthy plants. Mulch to a depth of three centimetres using pea straw or lucerne hay, both high in nitrogen, which will meet all the plants' nutrient demands, and keep them well hydrated with daily watering. Growing in a pot may require more watering, depending on the weather and the size of the pot. The smaller the pot, the quicker it will dry out, so the more watering is required.
A quick grower, rocket can be harvested from about a month and is best picked leaf by leaf. Choose the outer, more mature leaves first, which will free the plant's energy to focus on producing the next generation. This way you can look forward to a perpetual harvest.
Having said that, unless you have the appetite of a roaming herbivore beast, the rocket usually wins out in the end and seed heads begin to shoot sky-high - a sign of premature stress. To refocus energy back to leaf production, pick the seed heads down to their bases, and then work on regular picking. On the upside, the seed heads produce perfectly peppery edible flowers, and the very good chance of self-seeding plants to follow, providing more opportunities to graze on these peppery leaves.