When is a pseudobulb shrivelled?

[glossterline]

Hello learned ones!
I have often seen it written that a good indication of whether or not a plant needs watering is the state of the pseudobulbs. That is, new pseudobulbs will be shrivelled if the plants are dry.
I have two plants with pseudobulbs and I have to say that the latter are a bit folded or ridged. I am not sure when I would call them shrivelled. Hence my question: when is a pseudobulb shrivelled?

Thanks,


Les

[jerrymeola]

First a correction of your original premise.

A shriveled pseudobulb is not an indication of the orchid needing to be watered, it is an indication that the orchid is suffering from a lack of sufficient water for a long time. Once shriveled many orchids will never plump up again.

On Cattleya when ridges develop on the pseudobulb (ridges on the pseudobulb is the answer to your question of the meaning of shriveled), it most of the time indicates inadequate water. I find that it is usually the result from 'spritzing' 'misting' or similar light watering techniques. You do not develop rot by watering for a long time. Rot develops when the Cattleya is not allowed to dry sufficiently between waterings.

Water a long time so the roots have enough time in the water to soak up water and allow it to be transported by the root system to the plant. If only the outside of the root gets water it dries before the plant moves enough to the plant.

Oncidium are not quite the same. Many have ridges on the pseudobulbs as part of their nature. Ridges sometimes do not mean anything on an Oncidium. But again water heavy and allow the plant to just dry out before watering again.

Dendrobium - ridged canes should be avoided. It is a sign of inadequate water reaching the cane. Older canes will ridges 'shrivel' before they die and if the new growth is good on 3-4 canes then the old cane is just dying of age.

Phalaenopsis - here is the biggest problem for beginners. Soft drooping leaves with ridges is definitely a sign of inadequate water, but if the roots have been damaged from rot or from drying too heavily, then water can not be absorbed by the plant and watering heavy will only encourage more rot. Phals should be watered heavy when they have healthy roots and allowed to almost but not completely dry. When in doubt allowing it to go completely dry for a day or two is OK just not for too long. This is a good reason to avoid buying discounted Phal which probably are damaged.

These are the most common orchids. Other plants have needs that vary within this range.

[amersault]

i agree w/ Jerry - besides depending on the nature of the plant or if that occurs w/ age, a shriveled/ridged PSB is usually an indication of inadequate water.

this can sometimes be saved by slow gradual hydration - assuming that the plant is not too far gone in the drying process.

[amersault]

let me add to my last post -

by slow gradual rehydration, that may also involve more frequent watering so the plant has a good chance of 'getting a drink'. in my experience, increasing humidity by adding a tray or saucer beneath the plant has also helped tremendously.

[dr_frnkblck]

This is a pic of one my Brassia's that the ridges are natural and not from underwatering:

http://http://www.orchidgeeks.com/forum/picture.php?albumid=59&pictureid=573

This is an Onc pic where the bulb on the right is on it's way to pseudobulb heaven:

http://www.orchidgeeks.com/forum/pic...&pictureid=620

[jerrymeola]

to add to amersault's comments

watering more often certainly gives more water to the roots with the side result of the medium not drying as completely. A humidity tray also slows the drying of the medium. This is why I like a tray of water under orchids and do not like misting which dries too fast.

Keep all these suggestions in mind when you decide what to do. They all work so chose the one that feels most comfortable to you with your conditions and watering methods.

[glossterline]

Many thanks everyone. What you say is very helpful. The piccie posted by Dr frnkblck shows me a lot. BTW, what is the medium in that pot, because it looks like a pile of marbles to me?

Les

[jerrymeola]

The pile of 'marbles' you see is hydroponic rock, which is expanded clay. The same clay used for pots with air added. It is a different way of growing plants. The clay can wick up water at the rate of about 8%. The amount of water on the roots will always be close to 8%.

Water is keep in the saucer under the pot and the plant takes water at the 8% rate as it is needed. It is sterile so fertilizer must be used and salt (fertilizer salts not table salt) builds up and must by flushed out a couple of times a year.

The round marble look is from the Hydro-tron brand of hydroponic rock. Ali Flor another band works as well but the rocks are not as round.

[newbud]

So...could you possibly tell me the scoop on these. I water every/to every other day.