Roots that grow when?

[Helen]

I can't believe I'm asking this question.

Someone stated on another thread "That is why it's important to time to repotting to coincide with new root growth, so the new roots will be tailored to the new environment."

Don't roots grow ALL THE TIME??? I always thought they did...can someone explain the whole orchid cycle for me please? or direct me to some reading material on this?
Thanks!

[smartie2000]

Some orchids have growing seasons. This usually means growing in the spring and summer while slowing down in the winter.

[gerneveyn]

On an AOS Orchid FAQ, it is stated that new root growth is seen in the spring. Maybe I'm wrong, but I thought when the plants are budding or in bloom root growth is put on hold. On the AOS site, there's a monthly checklist for growing orchids, and in an essay it is stated that phalaenopsis exhibit "seasonal rooting behavior."

Here's the AOS Orchid FAQ site: http://aos.org/aos/uploadedfiles/docs/culturefaq.pdf
And the Monthly Checklist for May-June: American Orchid Society - Orchids

[dave b]

The comment you are referring to was said because the plant was going to be switched from standard bark mix to semi-hydro using clay pellets. The roots would have been 'used to' the bark environment, and may not adapt well to the s/h. As new roots develop, they will adapt to the medium or air they are in. Take a Phal in a pot that also has aerial roots. The roots in the pot adapt/form differently to the more constant wet environment as opposed to the roots in the air which are drier more of the time.

In some orchids, the roots grow all the time. But many orchids do go thru dormancy periods, in which root growth stops or at least slows way down.

Most orchids that come from warmer tropical environments (Phals, dendrochilums, ..tons more) have constant root growth. They naturally live in environments that stay warm and wet all year long (mostly). But, take many of the African orchids (Angraecoids, Aerangis...many more) that experience the wet season and the dry season. These types will go thru a dormancy period, and will need to be kept dryer and cooler for a couple months.

As you experience new orchids you like, search info on them to find out what cultural requirements they have. Check with your local library also. I am fortunate enough to have a couple local that carry many good orchid books. Reading thru many will begin to give one exposure to the variety of orchids and their culture requirements. College libraries are also awesome resources. You may not be able to check the books out, but you'll come across some amazing books.

[dave b]

[quote=gerneveyn;29943]On an AOS Orchid FAQ, it is stated that new root growth is seen in the spring. Maybe I'm wrong, but I thought when the plants are budding or in bloom root growth is put on hold. On the AOS site, there's a monthly checklist for growing orchids, and in an essay it is stated that phalaenopsis exhibit "seasonal rooting behavior."

This is something i have definately witnessed on most of my plants. There is only so much energy in the plant to do certain things...new leaves, roots or bloom. Not all at once. My phals will produce new roots throughout the year, but in spurts. They produce more in spring and summer, but i put them outside and they get rained on and start growing like crazy. This coincides with the post bloom, as most have finished up the winter/early spring bloom season.

[justatypn]

Tks dave great information for so many to learn when getting into orchids and forming the appropriate enviroment.

I love the aos info on monthly checklist... aos a great source of info...

[Helen]

Dave, Wow! what a ton of fabulous info you have given regarding roots....I'll definitely check out the cultures in more detail. Learning things everyday on this forum!
thanks again

[Helen]

Originally Posted by gerneveyn

On an AOS Orchid FAQ, it is stated that new root growth is seen in the spring. Maybe I'm wrong, but I thought when the plants are budding or in bloom root growth is put on hold. On the AOS site, there's a monthly checklist for growing orchids, and in an essay it is stated that phalaenopsis exhibit "seasonal rooting behavior."

Here's the AOS Orchid FAQ site: http://aos.org/aos/uploadedfiles/docs/culturefaq.pdf
And the Monthly Checklist for May-June: American Orchid Society - Orchids

Sarah, thanks very much for the link. I'll check it out.
All of you have been very helpful.

[Ray]

When plants' roots grow varies a lot in relation to flowering and seasons, and a lot depends on where the species in the plants' background grow. Plants near the equator, for example, are likely to grow continuously without much of a noticeable "rest period". Those emanating from the southern hemisphere, when grown up north, may show more active growth in fall and winter, rather than spring and summer.

Generally speaking, the most active root growth appears to coincide with active vegetative growth, and often slows during blooming cycles. However, the type-of-plant detail can play a role. Some plants bloom coincident with emerging new growths, others wait for them to mature, while others wait another year after that.

To clarify things and avoid misunderstandings, the advice about repotting when active root growth is happening is universally applicable, and is NOT limited to semi-hydroponics. In many cases, that switch to s/h culture is a relatively substantial one, so the advice is particularly applicable. On the other hand, if going there from soppy sphagnum, the switch is literally a "breath of fresh air" to the roots, making the timing of it irrelevant.

[Helen]

Thanks very much Ray, great explanation!