Herbs on balcony in August


I live in an apartment in East York Toronto. Our balcony faces west and gets sun after 3 p.m. during summer. In winter there’s hardly any direct sunlight.
My question is:
1) Is it too late to plant a coriander plant, a mint plant and a chili plant in one or two pots in the 1st week of August?
2) If I plant any of the three plants, would they grow to some extent for consumption before winter?
3) Can I put all three plants in one pot or need three different pots and how big do the pots have to be?


I suggest that you experiment to see if early August is indeed a good time to plant the herbs and the chili plant!  We can’t predict how cool late August or early September will be, but I’d be willing to bet that the herbs would grow quite well for at least a month-and-a-half.

Balcony gardening can be challenging given that on higher floors, there may be wind and dryness issues to consider.  Also, as we approach autumn, it’s not clear whether these plants, which need lots of sunlight in order to thrive, would do well.  For example, cilantro needs 4-6 hours of full sun each day, and mint around 3-4 hours in order to thrive.  Mint also enjoys part shade. Chili plants love at least 5 hours of direct mid-day sun each day so may be the trickiest to keep healthy on your balcony.  From the information you provide, your balcony spot likely gets about 3-4 hours of sunlight, starting quite late in the afternoon.  During the last part of the day, the sun would be low on the horizon.

Try to purchase small plants, and not to grow from seed, given the late planting date and the time it would take for seeds to sprout. For example, it takes around 7-10 days for cilantro seeds to germinate – taking you nearly into mid-August.  It would be best to plant each in its own pot, so you can move them around separately if you see that conditions aren’t ideal.  As well, mint is a bit of a bully so if all 3 plants were planted in one pot, the mint might take over. Plant each in a pot that is slightly larger than the root system – if you wish, you can grow a few plants in a larger pot.  Cilantro has a long tap root, so you may want to choose a taller pot.

Cilantro and mint grow quickly, and once the plants are established you can start harvesting a few leaves of each. Cilantro tends to bolt (go to seed) in hot weather.  Some experts recommend that it not be planted in the (hot) summer because it will bolt quite quickly – the tasty wide, flat leaves will be mostly replaced by lacy leaves that are much less flavourful, sometimes bitter.  If you find that the plant does flower and go to seed, the green seeds are yummy – they are the spice coriander and taste lovely scattered in salads.

The chili plants will likely be the most challenging to grow to the point where you can harvest the peppers.  Many chili plants need about 80 days to ripen – which would not be possible when starting the plants on your balcony so late in the season.  You can try bringing the plants indoor for the winter, too, although as indoor light is much weaker, they may not do well.

For all three plants use good well-draining potting soil and keep it moist, but not too wet or root rot could occur. Fertilize the plants with a general purpose fertilizer occasionally to promote the growth of lots of leaves.

For additional information, see the Toronto Master Gardeners Guide: How to grow culinary herbs   — this general article includes links to how to grow mint and cilantro/coriander.

All the best with your late-season balcony garden!

July 27 2022