How to Grow Your Own Fresh Herbs and Vegetables on Your Rooftop This Winter

Beginning a vegetable garden in the comfort of your Hong Kong apartment is a challenging yet wildly rewarding experience. Not only can you cook up the (literal) fruits of your labour into a delicious stew, but the more you flex those green thumbs, you’ll come to realise the amount of packaging and general food waste that is produced when shopping for veggies from the grocery store. There is no better feeling than doing your kitchen and planet earth a favour, especially when it comes with an endless supply of healthy ingredients.

Hong Kong has two well-defined growing seasons: summer and winter. The winter season generally begins after the mid-autumn festival and lasts until April to May. Because Hong Kong’s tropical climate tends on the warmer side compared to the rest of the world, there are lots of crops you can grow in this time that some countries would exclusively plant in the summer or spring. If you’re choosing the right crops that fit within your space requirements and Hong Kong’s planting calendar, there’s no reason why you can’t succeed.

Ready to embark on your own balcony or rooftop farm? Here is our beginner’s guide on how to start your fresh veggie garden this winter season in Hong Kong.

Carrots and Beetroot

Roots such as carrots and beetroot generally do well during the winter season and are perfect crops for beginner farmers. But, like many apartment dwellers here in Hong Kong, most of us may not have too much space for rows and rows of these colourful veggies. Luckily, these guys can thrive in pots and containers given they have enough nutrients and are placed in well-drained soil. All produce require sunlight to grow, so place these pots in a spot that will allow for UV rays to hit the plant.

Carrots and beetroots grow downwards, meaning that the entire carrot will be submersed in the soil. This means you will need to provide a deeper set pot for them to occupy, something like a 6- to 8-inch-deep pot. Depending on the variety of carrot or beetroot you choose to grow, you’ll need to account for how long they might need for harvest.

Dry soil is something you want to avoid with root plants, keep track of your soil moistness and top up regularly to ensure they drain before you decide to water them again. Carrots thrive in temperature from 16 to 25 degrees C and can tolerate slightly out of bounds temperatures well. Beetroot can also tolerate the same temperature conditions as carrots. If anything, keeping a cooler temperature is a problem that many Hong Kong farmers deal with, but it’s an easy fix with partial sunshades.

Time to harvest: Carrots can be harvested at any time but this may change based on variety (anywhere between 60 and 100 days from planting). You will get the most out of your carrots if you let them continue to grow and wait to harvest until they reach the desired size. Don’t be afraid to yank one out to make your size estimates! With beetroots, a third of their bulb will pop out from under the soil at around 56 to 70 days from planting.

Yau Mat Choi (Indian Lettuce)

Fancy a veggie stir fry? Indian lettuce, commonly referred as Yau Mat Choi, is the perfect leafy green to sow in the winter season and is recommended for beginners. Plus, it makes for a delicious lazy dinner stir fry!

Leafy vegetables like these are perfect for beginners to try out because they are hardy, which means there’s a higher chance of being able to bring something to the table. Lettuce roots tend to spread out horizontally as opposed to digging deep, so you have the option to plant multiple lettuce heads in one large pot or individually in separate pots. Yau Mat Choi lettuce grows well in temperatures from 15 to 25 degrees, but if it tilts below or above these temperatures, they may still be able to tolerate it.

Leafy veggies like Yau Mat Choi will require nutrients to ensure proper growth, so keep an eye out for Nitrogen, Phosphorus, Potassium (NPK) fertilisers, especially ones that focus on nitrogen. Aim to keep these plants watered well, and you can check if it’s ready to take in more water by sticking your finger an inch deep into the soil; if the soil sticks to your finger, it’s probably too soon, but if not, time to water!

Time to harvest: This lettuce takes no time at all to harvest, anywhere from 49 to 64 days from planting and you can have yourself a mature Yau Mat Choi to throw into the wok. Be sure to harvest before it grows a stalk, or else it will be too mature and may taste bitter.

Romaine Lettuces

Romaine lettuce is a variety of lettuce that grows a tall head of sturdy green leaves and firm ribs, so these would be your Little Gems variety, Rouge d’Hiver variety, or the common Winter Density variety that most people associate with “Romaine lettuce.”

These greens prefer a colder climate, anywhere from 7 C to 25 C would be a perfect growing climate for these greens and you might even wait a bit until November or December to plant these. They are fairly hardy but do require sun to grow to a large size. If your balcony is shaded, or is north-facing and thus doesn’t get as much sun as you’d like, you can expect slower growing heads of lettuce that can be harvested young – they will still taste great!

Like Yau Mat Choi, lettuces in general require lots of nutrients – especially nitrogen but be sure to pick a fertiliser that also has substantial amounts of potassium and phosphorus to encourage a healthy harvest. Since it’s also a lettuce, you can think of growing these romaine lettuces in individual pots just like you would with Yau Mat Choi, and water them well! Leafy greens are made up of water so you can probably guess they’re prone to wilting without enough water.

Time to harvest: Little Gem Romaine takes approximately 50 to 85 days to harvest from planting; Rouge D’Hiver takes about 50 to 70 days; and Winter Density takes about 60 to 70 days. But remember, if you know that your farming space can’t provide a ton of sun, it’s okay to harvest them when they’re still young.

Swiss Chard

Maybe this isn’t your first time farming, maybe you have the skills to try something that’s a tiny more challenging this season – heck, you just want something with a learning curve to feel like you’ve really earned it. No problem, while this plant is certainly growable and undoubtedly delicious, it does require slightly more than “beginner” levels of planning and effort to get right.

Swiss chards are quite hardy, but they’re growing difficulty is labelled as “intermediate,” partly because of how much they tend to thrive in larger garden spaces and not pots.

They require slightly acidic soil with a pH of 6.2 and 6.5, prefer colder temperatures of 5 to 18 degrees but can also tolerate slightly warmer climates. They need a constant supply of water and it’s important for the soil to be always moist. Their main requirement is nitrogen, but fertile soil is likely to provide the nutrients it needs. You can also opt for a fertiliser that you would use for the above lettuces for that extra kick.

Time to harvest: Anywhere from 50 to 100 days from planting, especially because these plants tend to germinate slowly. Like romaine lettuce, if you know you can’t provide these plants with too much sun, you may have to manage expectations and harvest them young as they may not reach their full potential size.

Cauliflower

Not enough of a challenge? If you want to compete and fend off unruly and uninvited crawlies that are trying to sneak a bite of this super food, you are more than welcome to give it a shot. Rooftop gardens and balconies don’t typically host as many pests as farmland, since they are far removed from the ground – where the bugs usually are. But where the food is, the bugs follow.

Cauliflower are all viable crops to plant in the winter season, but not typically advised for beginners because they are incredibly nutritious, take up lots of space, are high-maintenance, and are absolutely loved by pests. If you want to give this a try, plant at your own risk.

If you have the room on your rooftop, you can try planting cauliflower in containers, which will need to be at least 8 inches deep and 20 inches wide. They require constant moisture and are incredibly greedy when it comes to nutrients. You will need to feed them with a foliar feed of compost before they start to head, and they are very susceptible to boron deficiency, which occurs with acidic soil.

Time to harvest: Harvesting time for cauliflower is typically quite long, somewhere between 80 and 90 days.

Herbs

Finally, if you don’t have too much balcony space, or if you don’t have a balcony at all, you can opt for a low shade tolerant herb such as rosemary. If you have limited balcony space or a bright window that you can leave open most days, you can opt for mint.

Herbs are a lovely addition to your kitchen, no matter what it is you’re cooking. It’s always nice to have some of these bright flavours available to you and they should never be overlooked.

Mint tolerates light frost and hard frost, and you can look at mint as a sort of weed. They are a perennial plant and often overtake beds and suck up nutrients from the soil before your other plants get a chance to eat – so if you’re thinking of planting mint, make sure it’s not sharing a container with anything else. They’re pretty hardy and can grow in most conditions. All you have to do is water them often to ensure the soil is moist.

Rosemary is also a perennial bush herb that will do very well in the Hong Kong climate. It can also tolerate light shade, so feel free to put it next to a window indoors if you can’t find a place for it outdoors. You can think of rosemary as a succulent, they can manage without constant watering and thrive in soil that is not too rich in nutrients.

Harvesting time: Perennial plants like these are harvestable all year round. They will continue to grow and stay a staple in your kitchen for as long as you want them there.

A very special thank you to Godfrey from Living Farm for these specific-to-Hong-Kong climate farming tips! If you have any enquiries about starting up your rooftop or balcony farm, try reaching out to your local farms to see if they would be willing to share some tips and tricks.