Susanne, it isn't a new idea but under certain circumstances it can help, not so much to control height, rather, to encourage less leggy plants as you mentioned.

The initial observation was that tomato plants being grown along the narrow aisles of greenhouses were more robust and that's b'c as the workers went down through the aisles they were brushing against the plants on the aisles.

The phenomenon is called thigmotropism, meaning response to touch.

Cornell tried to get all the commercial growers to use a broom handle or whatever, and I knew quite a few of those commercial farmers and they tried it for a while, but for many of them the extra time taken to do it wasn't, in their opinion, worth it. And that's b'c they had to spend hours upon hours watering their greenhouse plants at the same time.

YOu certainly can try it at home, but a fan on low speed will do just as well.

And yes, my commercial farmer friend who allowed me to use his greenhouses to transplant my tomato seedlings and then grew them on for me was one who participated in the Cornell Coop Ext idea of brushing the tops of the plants so I saw the results, such as they were.

And you could see the same thing on the plants that were grown in front of the large blower fans in the greenhouse used for air circulation and venting.

Carolyn

I thought I was the only one who did this! I read an article in our local newspaper about 10 years ago about brushing the top of your tomato plants to grow sturdier, stonger plants and have been doing it ever since. I don't use a tool, but just a finger lightly across the seedlings to simulate the wind. I do this everytime I pass by them.

We use fans. I think many do.

Dave

Agreed. I just attached a small fan to my light rack and plugged it into my light timer. I noticed a big difference between my plants and my mom's plants hers were started about a week before mine and mostly the same varieties. Mine are very stout and bushy and hers are tall and spindly.

I'm going to try and rig a fan, but if it doesn't go to well I'll just brush my seedlings.

Thanks for the replies, everyone. I thought this technique or some variety was probably known and used, but it's not mentioned a lot on the forums. Not that I've seen, anyhow.

And as soon as you guys mentioned the fans the light bulb went off for me and I remembered reading that before. Just hadn't remembered exactly WHY people used fans.

Last year I had a good bit of trouble keeping my tomato and squash seedlings from getting leggy to the point of breaking. A fan and a little petting are on the schedule this time around... :^)

Susanne

How soon after germination should one start this? How high should the little guys be to do this?

Sounds right to me. Aren't you supposed to leave some play on new planting supports (tree's) so they root in? The movement of the tree by the wind activates the roots to set in and get deep. If the support it taut then tree will not root in a quick.

Cleo,

The text that goes with the video says "Begin treating when the plants are about 2-1/2 inches tall."

You can read all the instructions at the link below.

Here is a link that might be useful: Brushing instructions

I use little 5x5 (or 6x6) computer fans I get cheap at one of those surplus stores. They're also helpful in the earlier stages, keeping the dread damping-off at bay. GaryStPaul

theres also a technique called LST or low stress training. I havent done this with tomatoes yet, but basically when your plants are at about 8 to 10 inches tall you tie the plant over. the best way in my opinion is to have one tie at the base of the plant and one at the top of the plant pulling in opposite directions. By doing this the top of the plant is pulled below multiple nodes of the plant. When this is done auxin growth hormones are then redistributed to the rest of the plant causing the lower growth to grow with the same vigor as the main growth top once did before this process. This provides for a nice bush. as the plant gets bigger further tieing is usually necessary. The above processes are quite necessary still though in my opinion. The process of exposing a plant to the elements ie. wind turbulence will provide for a hardier sturdier plant.

peace

I have 6" fans that have clamps on them and they work nicely on my 2x2" supports on my growing frame. The day after I transplant them the first time (from seed starting flats or small containers with drainage to 2" cells) is when I put them under fans on timers. I really notice quite a difference between the plants near the fans, and the ones further away. I plan to add another fan to the center or the other end of each shelf so the ones on the far end get the air movement. I will have to experiement to see what works best.

Bets

Some of these things (LST, supercropping) sound sorta sadistic - like Chinese foot binding! Yikes. I can only give so much "tough love" to my babies. But I will turn a fan on them after their first potting up - that tough I can be!

It sure has been worth it for me. I have one greenhouse just for tomato starts (perhaps 40 varieties) and once they are up about 4 inches I brush them every morning and every night. I actually picked up this strange foam wand thing at the dollar store. I do feel a bit badly - beating my babies like that, but it's kind of like hardening them off and my customers love the healthy, stocky plants. I've been doing it for @ five years.

I see that large commercial growers are now using strips of plastic that hang down like a car wash and they mechanically go back and forth. I imagine the physical touch has more effect than a fan.

(HI CAROLYN - I bought your book - LOVE it.)