Rocket is great for enlivening a salad alongside milder greens. Known as arugula in the US, this is a popular crop that is just as good for beginners as it is for more experienced gardeners. Read on to learn more about this herb, and how to grow rocket where you live.
What Is Rocket?
Before we explore how to grow rocket, it’s essential that you know what I’m referring too! After all, there are two different plants known as rocket, both of which are members of the mustard family: wild rocket and salad rocket.
Wild rocket has the Latin name Diplotaxis tenuifolia. It is also known as perennial rocket, because it has a lifecycle that takes place over a number of years. It should last for several years in a suitable location in a garden.
Salad rocket, Eruca sativa, is an annual plant, meaning that it will remain in the garden only for a single growing season before it must be sown again. This option offers more delicate plants, with a somewhat milder flavour and there are a number of different varieties to choose from which differ somewhat in their leaf shape and flavour.
Both types of rocket are useful cut and come again crops, whose leaves can be picked and eaten little and often over the course of the growing season. However, the former crops over a much longer season than the latter.
View our growing advice section for more information.
How Long Does Rocket Take To Grow?
Rocket is quick to grow and can be harvested a little perhaps even as soon as 4 weeks after you first sowed your crop. The quick results mean that rocket of either kind can be a great choice for new gardeners, who will want to see results from their efforts sooner rather than later.
How To Grow Rocket
It is very easy to learn how to grow rocket, no matter where you live. This is a crop that you can potentially grow even if you do not have your own garden, as it can be grown indoors relatively easily on a sunny windowsill – perhaps alongside lettuce and other cut-and-come-again crops. Here’s how to grow rocket in a couple of steps.
Choose The Best Variety For You
Of course, if you would like to know how to grow rocket at home then the first decision that you will have to make is which type of rocket is right for you. As mentioned above, there are two types of rocket, perennial and annual and both options have both downsides and benefits.
Perennial rocket has a somewhat stronger flavour, especially through the summer when it is likely to become more bitter. However, you can harvest it over a much longer period – even over the winter months if you grow it in a polytunnel greenhouse, or under cloche protection. Of course, as a perennial, it will also come back year after year.
Annual rocket only lasts for a single season, and can be harvested only up until the point where it flowers. It can have a tendency to bolt in hot weather. However, it does have a slightly milder and more delicate flavour than the above.
Once you have decided which one of these to grow, you can begin to think about sowing your rocket, and can decide where you will do so.
Sow Your Seeds
Rocket can be sown directly where it is to grow outdoors, or sown undercover, or indoors. Which option you choose will depend on your preferences, where it will grow exactly, and when you want to harvest your crop.
If you decide to sow directly outside where the rocket is to grow, then you can generally do so any time between April and September. This might involve sowing directly into the soil in a garden bed or border, or sowing the seeds into a container on a patio in order to grow this crop.
If you are sowing in a bed, it can be a good idea to sow the seeds into shallow drills around 1cm deep, in rows that should be around 15cm apart.
However, you can also simply broadcast or scatter the seeds over the surface of the soil or the growing medium in a container. In either case, the seeds should be lightly covered, then firmed gently into place. Remember to water them in well to ensure good germination rates.
It should take no more than a few days for the rocket seeds to germinate. They should be protected from slugs and snails and other pests, and once they reach a large enough size to handle, they should be thinned to around 15cm apart.
Remember however that thinned seedlings should not be discarded, as these are perfectly fine to eat and can be a great addition to salads.
To enjoy harvesting rocket over as long a period as possible, it is a good idea to sow just a small amount of rocket seed every few weeks. Successional sowing means you can harvest for longer and will not end up with a glut.
If you wish to extend the season and harvest rocket as early as possible in spring, and perhaps later into the winter too, then it is often a good idea to sow rocket indoors.
In spring, sowing indoors or undercover in a frost-free location means that you can enjoy a harvest earlier than you would be able to do if you waited until it was time to sow seeds outdoors.
You can sow indoors in February or March for an earlier spring harvest. And you can also consider sowing in August or in September in order to enjoy rocket harvests well into the winter months.
I sow rocket alongside other leafy greens in late summer in my polytunnel and can harvest them right up until Christmas and sometimes even beyond. Sowing in the shoulder seasons can make it easier to avoid the bolting issues that can commonly occur over the hottest summer months.
Stay On Top of Maintenance
Of course, knowing how to grow rocket is just the beginning. Although rocket does not require a lot of work, there are a few jobs to think about to make sure that you get a good harvest from this crop.
Sunlight and Shade
One important thing to think about when growing rocket is how much sun it receives. In warm weather, rocket prefers to be growing in a somewhat shaded spot. This stops it from becoming tough and too bitter, and from bolting to flower and set seed.
Of course, you should position summer sowings in places where they get some light shade from other plants. And cover the plants with cloches or row covers, perhaps. If you are growing rocket in a container, it can be a good idea to move it into a shadier position when the weather is particularly hot.
It is very important to make sure that rocket, especially annual rocket, gets consistent moisture throughout its growing season.
The soil or growing medium in which the rocket is situated should be kept consistently moist at all times. This means watering during any dry spells, of course, and remembering that plants in pots will generally need watering more frequently than those in the ground.
If rocket dries out too much, it is more likely to bolt and run to seed prematurely. Which, as mentioned above, when growing annual rocket, means the end of the harvesting period.
Pinching out each of the flowering stems of rocket plants allows you to crop the plant for longer. However, this is not always something that you should do. You might wish to allow the plant to set seed, because rocket can often, when positioned in the right location, self-seed readily.
After annual rocket flowers and sets seed, it will have completed its lifecycle and will die. It can simply be removed form your garden and added to your compost heap.
Perennial rocket will remain in situ as it can live for several years. After flowering, you can continue to harvest the leaves, and can trim back the plants if they get to large and unwieldy. Harvesting or trimming will encourage the growth of fresh new leaves on these plants.
Harvest Your Rocket
As mentioned above, you can begin harvesting leaves early – typically around 4 weeks after sowing your rocket seed. If you sow batches successionally, you can potentially harvest rocket right through from June to December and perhaps even beyond.
Pick leaves little and often from your rocket plants, and new leaves will grow. But do not take too many leaves from each plant as if you harvest too much at once, the plant will be slow to recover and regrow.
Even with annual rocket, which can only be harvested over a shorter time period, you should be able to harvest 2-3 times before the plants begin to flower and the harvest is over.
How To Use Fresh Rocket
Once you’ve followed my steps on how to grow rocket, you get to eat it! Young and tender rocket leaves of either variety can be added to salads. Older leaves can be lightly cooked and used in stir-fries, lightly steamed, or sautéed in an olive oil. You can also make a peppery rocket pesto, or use rocket in other sauces or condiments.
Elizabeth Waddington is a writer and green living consultant living in Scotland. Permaculture and sustainability are at the heart of everything she does, from designing gardens and farms around the world, to inspiring and facilitating positive change for small companies and individuals.
She also works on her own property, where she grows fruit and vegetables, keeps chickens and is working on the eco-renovation of an old stone barn.
To get in touch, visit https://ewspconsultancy.com.