Exactly 5 weeks ago, I got a batch of Angraecoid plants from Malala (Madagascar) arranged by a friend who ordered a batch of plants for a number of people (all legal of course, with all the paperwork). I had done this in the past, and often it took a long time for plants to develop new roots and grow on properly. Sometimes 3-4 month and about 1/3 of the plants would not make it. If the plant did not grow on before winter, it would likely not see the next spring.
Just before the plants arrived, I came across an article about Trichoderma which claimed that a) it improved root development, b) it makes plants more resiliant to diseases. I managed to buy a Trichoderma/clay powder to be used for watering and decided to try it.
As usual, the imported plants had hardly any life roots. No roots that were growing.
Steps I normally perform on imported plants
What I did additionally
- I prepared a sugar or mollassis solution and dipped the green parts of the plants into it
- After two days, showered the plants heavily to get all the sugar off (otherwise there will be problems later)
- Repot or mount
- If the plants are in really bad shape, I spray with AgroBest Envy (an anti transpirant, which can reduces moisture loss in plants). In this case I did.
- I then prepared a Trichoderma solution (using Trichoderma/clay poweder)
- I soaked the plants in the solution on March 25th
I watered about every 4-5 days. In effect this meant that the mounted plants got fairly dry: the moss they are in would be bone dry on the surface after 1-2 days (but there would still be some moisture).
Then I forgot about the plants: as expected, they did not produce new growth and there was no visible sign of new root development. I also didn't apply the second dose of Trichoderma 7-10 days later as outlined in the instructions.
Last week, my friend dropped me a line to see how my plants were doing. So I had a closer look: I was amazed to see that half of the plants had developed masses of new roots hidden in the moss. Mainly new roots coming from the base of the plant (see pics, taken after watering such that the roots are more easily visible). In some cases an inch of new roots grew in less than 4 weeks.
The other 50% may have developed roots too, but as they are mounted with spaghnum the root growth is not as visible. I also noticed that all plants are now starting to grow.
Of course this is not scientific, but I am amazed how well and quickly the roots are developing compared to the experience of past years (in particular with plants from Malala). Plants from that source at a minimum took 2-3 months to develop new roots, sometimes new roots would not develop until the next grwoing season or not at all (with the plant dying). Also comparing notes with my friend: her plants have not yet developed new roots.
Note that the roots have a different look to roots on other plants that I have grown on in the past: they have lots of white "hair" on them (in other words the roots are feeder roots).
I gave the plants another soak in Trichoderma solution this morning and I am about to try Trichoderma on the rest of my plants in the greenhouse.