Recently picked up gardening again and started with a small but diverse range of flowers,herbs and vegetables. The last time I did gardening was back in the 80's I have been educating myself as I go along and already controlled a outbreak of Green looper caterpillars. So might be green(not a bad word here) in certain terminology. The main point is these plants have been with me for about 2 months and getting established.

After the insects signed a peace treaty I started pruning some of the basil plants and even some of the thyme. The results have been awesome with the plants growing back with renewed vigour.

The Vietnamese mint/coriander(Polygonum odoratum) has been growing nicely but getting a bit tall and not as bushy as I would like. In my mind there is a fundamental difference between Basil and Vietnamese mint as the mint does not branch as much as Basil. The mint seems more like a true mint even though it is not a mint at all. Thus creepers instead of branching out.

I been searching on google on pruning tips for the Vietnamese mint but its either in Vietnamese or very light on details.

So in a nutshell.

  1. Any specific pruning techniques required for the Vietnamese mint?
  2. In general pruning seems to help the plant by removing the dead/sick/infested parts of the plant and this mean the roots can use the extra energy to produce better growth. Is this theory valid for all plants.
  3. I tend to prune every 2-3 weeks and not heavily just take some tips away to ensure the plant does not grow tall top heavy and yields less than I would like it to. Is it too much or too little? Most advise mention a couple of weeks and a couple in mind is 2... 3 is a crowd but I am just pedantic at times.

Any pointers would be appreciated.

1 Answer 1


Vietnamese coriander is now known as Persicaria odorata - there is conflicting information on the internet regarding its height and spread, with one site describing it as a low growing ground cover, but the general consensus seems to be that it reaches around 30 cm, with a spread of up to 25 cm. If yours is a bit lanky, it may be it's not getting enough light or doesn't have enough room around it if its hemmed in by other plants. If its in a pot, it may need repotting quite frequently to allow sufficient root room. As for pruning, none is necessary, as such - 'pruning' consists of clipping off parts for culinary use; pruning out any diseased or dying parts is a good idea as a general principle for all plants. Image and general info here http://www.manorfarmherbs.co.uk/+/herbinfo/vietnamese_coriander

  • Might just be that. The instructions that came with the plants(little inset) said I should keep in partially shaded area and avoid extreme direct sunlight. Thus it is standing under my shade netting on the balcony outside. It is in a large pot either 51/41 cm diameter. I have built a grow cage in my garden which uses very light shade netting as my location in Western Sydney can easily reach around 38-40 degrees on a hot day with no cloud cover. I layered some shade netting which only blocks 10% (i.e. 90% penetrates ) of sunlight. My leaves plant is definitely not showing purple as per link.
    – Namphibian
    Commented Nov 18, 2016 at 2:57
  • If you can, can you add a photograph of your Vietnamese coriander? Just to make sure its the same plant I'm talking about.. it might not like strong sun, but it does need reasonable daylight
    – Bamboo
    Commented Nov 18, 2016 at 14:06
  • Yeah they they same the plant started developing the purple colouration over the last two days. I also moved into the shaded grow box I built and it seems to be functioning a little better.
    – Namphibian
    Commented Nov 20, 2016 at 7:28
  • Bamboo thanks a million the plant is doing so much better. Your advise about moving it into a new position was just what she ordered.
    – Namphibian
    Commented Nov 24, 2016 at 18:01
  • Thanks for the advice the plant has gone from stringy to a bush in less than 3 weeks. It was definately in the wrong space. Level 1 gardener badge achieved.
    – Namphibian
    Commented Dec 1, 2016 at 10:08

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.