Dendrobiums blooming, spiking, and growing - Page 4 - Orchid Board

MJSK · #31 05-21-2012, 01:28 PM

Again, thank you for the advice. I have been monitoring dryness misting the Dens, not just watering them when they get dry near the window on sunny days. They are all in the greenhouse (accept the 2 that still have flowers) where they get a lot of light. I was going to put my Den. Nobile's outside in my garden along a low brick wall for protection from too much wind knocking them down. They would be in direct sun from dawn to maybe about 3 PM when the sun has moved into such a position that if there are right next to the wall, they will be in shade. I have an olive tree and some citrus trees that live in my greenhouse in the winter and live outside in the summer. Perhaps if I position them under these plants they will get some filtered shade from the leaves. As this is right next to my vegetable garden which is often watered by a sprinkler or 'water wand', the Dens. will get plenty of water. I live in Boston where the summers can be hot and humid. I figure with the heat water will evaporate quickly and the humidity will help if they get a bit dry between watering. I will also of course pay attention to the weather and water accordingly as I do all summer. Perhaps I will only put one outside this summer to see how it does, particularly since I don't want them to get aphids or spider mites. I am also worried about storms that could knock the Den over and possible cause damage to the canes. I was going to put the orchid, which is in a plastic pot, nested inside a heavier clap pot for support. I will post results.

NYCorchidman · #32 05-22-2012, 12:35 AM

You're most welcome.
Well, mine get about half day sun and they grow and flower amazingly well. so yours might do even better!

You can actually grow them in light shade while actively growing, but not too much shade under tree. make sure some direct sun is coming through the trees, otherwise, just place them in good light.
After growth stops in August or September, make sure they get full sun with no shade. higher the light, better the flowering!

As to watering, while they are actively growing, do not allow them dry between watering. maybe one day won't hurt, but water them daily for best result. humidity in the air does not replace watering.
You can reduce watering once the weather gets quite cool or cold. then maybe once a week/more or less depending on the growing condition.

Bugs- outside might be better for them in the summer. but bugs will come. by heavily misting or hosing the whole plant often, you can get rid of these pest usually. but if you want to save all the concerns, maybe indoor growing is better. You still want to check for these bugs though!

I repot all my nobiles in clay pots because they need lots of water but need to be drained and dry fast as well. Also, clay pots are heavier so plants do not get knocked over easily. My oriental smile fantasy is very tall for its type. I knocked it over a few times and lost some leaves at that. so I put the whole thing into a larger super duper heavy pot. no more knocking over since!

For outdoor in the summer, if you worry about strong winds knocking them over, make sure the entire pot is secure somehow. As long as the pots are secure, plants won't get damaged easily. If there's going to be a terrible storm, then maybe bring them in or cover up just to be safe.

If yours have lots of canes full of pot, I would suggest putting them into a larger pot. You might have heard dens like to be potbound. that is one of the biggest bogus out there. no plants "like" pot bound. it does make waterin job easier for us though. definitely not good for the plants.

Dens can be sensitive to repot, so try not to remove any old media but just take it out the current pot trying not to mess with the roots too much, then just slide the whole thing into a larger pot, then fill the gap with fresh media. they grow tons of roots all over!

Make sure fast draining media is very important because you want to water these A LOT!!!

MJSK · #33 05-22-2012, 01:04 PM

Again, thanks for the information. I am going to try one of my Den. Nobiles outside, just to see how it goes. We have some fruit trees near the vegetable garden the cast some shade in certain areas as the sun moves during the day so I have a lot of options for placement. Watering will be no problem. It is good to know to give them more light after they stop growing in August. The hardest thing for my to control is watering in the winter when the air gets so dry I always feel like I have to water, I have to fight my natural instinct.

As far a bugs go, I will keep an eye out for infestations. I tried to grow Cynoches wine delight twice. Both plants suddenly developed aphid infestations (indoors) while none of the other plants around them did (and the plants were close, touching each other.) It was so bad, I got rid of them. Last Fall, I discovered that a Paph that I had for six years (a faithful bloomer) had scale. It was so bad I was going to throw it away but then I drenched to plant with a Neem based insecticidal soap followed by a drenching spray of horticultural oil and the scale was killed off. I am confident that I will be able to take care of any insects.

I have repotted some of my Dens recently using repotme.com's Dendrobium Imperial orchid mix so hopefully this mix is fast drying enough. Some of the plastic pots I used are designed for orchids and have slits cut along the sides of the pots. Hopefully the Dens will like it.

I had read about Dens liking to be potbound. It is amazing at the conflicting information I have come across in my reading. Although I have read that there are more than 40 different groups within the dendrobium species, so I guess they are very diverse.

NYCorchidman · #34 05-22-2012, 01:26 PM

Don't worry about winter watering yet.

It's just that when the weather gets cold and there is too much moisture in the media, things start to get bad.
plus they don't use much water while in dormant.

Plastic pots with extra slits around the sides sound good. When the weather gets hot (and when pots are placed outside) I'm sure things will dry out fast enough.
Just make sure water a lot in the morning then just in case.

I opt for clay pot for even faster drying. I do not remove old potting media when I repot nobiles, so I want things to dry out fast so the center do not rot. so far so good!

Remember no plants "like" to be pot bound. It is for our convenience.

Congrats on gettig rid of scales on your long time loved paph! It would be a heartache to lose something like that. So the plant didn't mind being soaked in all those stuff? I'm sure better than being sucked up by all the bugs.

Bugs seem to select certain plants over others. have no idea why. just get rid of them as soon as you find out. They can multiply fast!
I leave my window open all the time except when it rains like this week. I do find aphids flying in every once in a while. I hand pick and squeeze them to death every time I find them. not too many, like 1 or 2 a month so far. not bad at all.

MJSK · #35 05-22-2012, 04:02 PM

I am trying not to water too much (I am very bad at that and have killed many orchids as a result - thank you for the advice on that). As NYC and Boston are relatively close, then you know we had an unseasonably warm winter and the plants in my garden were almost 1 full month ahead of their regular schedule. We had a lot of really warm and sunny days and I did water my Dens. a lot. We went back to more normal temperatures and I have cut back on the watering. I don't think I damaged the plants as one of the ones I repotted was the Den. Red Emperor 'Prince' and the roots looked great.

Just for your information, I used Bon Neem insecticidal soap and Horticultural Oil (both Bonide brand products). The products are marketed as 'organic'. I bought the spray bottles and made sure the plant was drenched on both sides of all the leaves, the stems and the top of the potting mix. I think there was enough spray to penetrate down into the mix a bit as well. I let the plant dry before drenching with the other product. I was lucky on the day I noticed the scale that it was warm and I sprayed them outside, after taking note of the wind direction as I didn't want to spray myself. I have also used rubbing alcohol on mealybugs as well but I think coating the plant with the bonide products works better. The horticultural oil coats the insects and kills the adults, larvae and eggs.

I did remove all of the old potting material when I repotted as every book and sites on the internet tell you to do this. I soaked the mix in a solution that was 1 Tablespoon of Superthrive in a gallon of water for root growth. the Yamamoto cultural information said to not water for a week or two (which I read AFTER I gave them a good watering after repotting), but hopefully I haven't hurt them too much. On one of them there is a leaf that is turning yellow and will probably fall off. I don't think this is the correct time for that to happen, however.

MJSK · #36 05-22-2012, 09:11 PM

This long exchange of messages has been really good for me to consider how to take care of my Dendrobium Nobiles. I have almost 80 orchid plants (a few Oncidiums, a lot of Cattleyas, Laelias, Phrags and a hodgepodge of other random hybrids and species) and the information in your many posts has been helpful for getting the 'picture' straight in my mind. The concept of watering everyday, but also letting the water drain quickly so the roots dry a bit is different than just keeping the plant wet (as I have been trying to do with my Phrags.) My Den. Noid that started my interest in Nobiles bloomed beautifully without much help from me. With very focused culture instructions I am looking forward to see what happens next year. My mother gave me 2 noids that were keikis from her plant. I gave one to a friend after it flowered earlier this year and a month later, that one budded and flowered again. Unfortunately the one I kept did not.

Anyway, thank you again.

NYCorchidman · #37 05-23-2012, 03:00 PM

Thank you for the information.
I haven't had any major bug issues and I'm not sure if I want to get into chemical stuff, but I will keep that in mind just in case as I do have some red spider mite issues every once in a while. I normally manually kill them off at an early stage.
One time, I had to get rid of two gardenia as red spider mite issue got too bad and I didn't want to risk my orchids.

So you sprayed with insecticidal soap and then soaked with neem oil? I just read that neem oil can affect leaves on certain orchids that the leaves show irregular yellow patches. I'm glad yours is fine.

Nobiles require a lot of watering while actively grow. They will survive with less water but leaves will get kinky and plants will fail to reach full potential.

Keeping them moist all the time will rot their roots. Although some might still survive especially in the growing season.

The wild ones live on trees with humid air plus monsoon while they are in active growth phase. they get poured down and then dry up quickly on a daily basis.

These grow and bloom very easy and nicely. they just need lots of water, high light and then cool rest. You get these three factors right and they grow and flower without fertilizer. Mine all do amazingly well.

Withholding water after repotting is recommended because root rot can develop since some if not many roots may get damaged while repotting.

Regarding removing old media, old media can be mushy (bad because this means poor drainage and also may stay wet too long which leads to root rot), accumulated salts and potential disease causing agents..
So when you repot, you don't have to unless old media is in really bad condition. Sometimes dendrobiums just die after repotting if roots are messed with.
so I do not take a risk.

MJSK · #38 05-23-2012, 05:46 PM

The insecticidal soap that I used had Neem already as an ingredient, I didn't use it separately. I think you have to dilute it if you are going to use it anyway. I used the insecticidal soap and then after it dried the horticultural oil.

I hope I didn't mess with the roots of my repotted dens too much, they were in good shape, I was just trying to get some rotted and old potting material off the roots.

I feel confident about the correct way to grow Den. Nobiles and will hopefully have great results. I did purchase Jack's Classic Orchid Bloom Booser 3-9-6 fertilizer from my local garden center and will probably use it as the Yamamoto culture sheet recommend a low Nitrogen fertilizer. You don't use any fertilizer at all?

NYCorchidman · #39 05-23-2012, 05:56 PM

Quote:

Originally Posted by MJSK

The insecticidal soap that I used had Neem already as an ingredient, I didn't use it separately. I think you have to dilute it if you are going to use it anyway. I used the insecticidal soap and then after it dried the horticultural oil.

I hope I didn't mess with the roots of my repotted dens too much, they were in good shape, I was just trying to get some rotted and old potting material off the roots.

I feel confident about the correct way to grow Den. Nobiles and will hopefully have great results. I did purchase Jack's Classic Orchid Bloom Booser 3-9-6 fertilizer from my local garden center and will probably use it as the Yamamoto culture sheet recommend a low Nitrogen fertilizer. You don't use any fertilizer at all?

What does horticultural oil have in it then?

I fertilized maybe once a month? I know they were fed weekly when the new shoots were showing to encourage better growth, though I'm not sure if it makes much difference. then once they started to get going, they grew just fine with either no fertilizer or once a month from May to July.
The ones that were fed and not fed did not show any difference in growth and flowering. how odd, isn't it?
(by the way, one of my Oriental Smile Fantasy grew up to 3 feet without regular feeding. While my other one is about 18in. just individiual characteristic I guess)

Then I washed out the potting medium by soaking in clean water everyweek to make sure nothing is left behind.
Explosion of flowers in the spring!!!

MJSK · #40 05-23-2012, 08:26 PM

Horticultural oil is used in outdoor growing a lot. I know that horticultural oil is used on fruit trees as they get a lot bugs probably due to the 'sweetness' of them, or so a 'knowledgable' person told me. The oil coats the surface of the bark so that the bugs cannot dig in and it coats eggs so they cannot hatch. When I first heard about horticultural oil, I think the oil was petroleum based so I stayed away from it. I used Bonide brand on my orchids (here is a link to the labeling: http://www.bonide.com/lbonide/backlabels/l210.pdf. The first thing is says is that it is for organic gardening, and you can see that it is used to control a lot of different bugs. I stay away from chemicals. I knew someone in the mid 70's who had been exposed to agent orange in Viet Nam and have always been wary since. The only thing I put in my garden is compost and I use an organic fertilizer on my tomatoes as I found that the calcium seemed to produce better fruit, again a tip from a 'knowledgable' person.

One of your Oriental Smile Fantasy orchids grew to 3 feet?!?! Wow, that is a big plant. I don't know if you have ever taken a look at a book called 'Dendrobium and its Relatives' by Bill Lavarack, Wayne Harris and Geoff Stocker. It is quite interesting. Some of the Dendrobium species in the wild get really big.

I have tend to fertilize twice a month during the warmer months of more active growth and I do flush the pots with water to wash away salt build up. You can see the salt building up on clay pots of plants that are over fertilized. I also watch for leave tip changes. During the winter, I stop fertilizing as the days are so short, the plants probably cannot utilize the nutrients. I will probably fertilize this summer, perhaps I will do an experiment by not fertilizing one of the Den Nobiles that I have that has already flowered to see if there is a difference. I don't have any duplicates right now.