From the BBC:
Title:
Fungus network 'plays role in plant communication'

"Plants can communicate the onset of an attack from aphids by making use of an underground network of fungi, researchers have found."

http://www.bbc.co.uk/news/scie...

They found that if
- you grow five broad bean plants fairly close together,
- and let three develop mycorrhizal networks
- but prevent that in the other two plants,
- and put bags over each plant so they can't use through-the-air chemical communication,
- then infest one of the networked plants with aphids
...
the infested plant deploys chemicals that repel the aphids and attract parasitic wasps that are aphids' natural predators (known process)
... but also ...
the other two networked plants deploy the same chemicals even though they had no aphids.

The plants with no mycorrhizal connections did NOT activate their anti-aphid chemicals!

Nature is clever.

Huh. That's interesting. It also goes a long way towards explaining why my outdoor plants never show signs of aphids, but let me bring one indoors? Yow! Aphid city!

So maybe we do the right thing by planting out clumps of our WS sprouts.
I wonder if this means--- we should plant two tomato plants per container, rather than just one?

The author mentioned some suggestion like having ONE plant in a field that was extra-vulnerable to aphids. That way, they would attack the vulnerable plant first, and trigger all the plants in the field to unleash their protective chemicals.

But if there were no aphids at all, the plants would not use up the energy and nutrients consumed in the anti-aphid-defense. They only go to war when they need to!

I have never been able to go back and find again something that I read somewhere. It claimed that some species actually do BETTER as seedling if they are crowded up against other seedlings of their own species.

They are actually encouraged by close neighbors, at least as seedlings, if the neighbors are the same species. Or so he or she claimed.

Cooperative crowding? There was a name for it, but I forget what that was.

I could believe that Lobelia work that way: I've never seen a single Lobelia, only masses. Maybe daisies?

I wonder if it works for anything besides aphids?

LOL! I have foolishly planted single lobelia! Before I knew to clump transplant them! That was a chore.

So everytime we throw a bunch of seeds in a tray and let them germinate and grow on as seedlings they benefit from crowding? Good to know! I do it all the time! Today I was transplanting my celosia with about 200 in a small tray! what a chore.

Only thing I know for sure about that is that it certainly doesn't work for alfalfa! Did you know that you can't plant more alfalfa seed in an existing alfalfa field? The plants give off some chemical that inhibits germination in the new seed. Sigh, wish it had that same effect on weeds in those fields.

So, do you mean you can't plant alfalfa in the same place the following year? So you are FORCED to rotate crops? Or do you mean you
can't plant more seeds to fill in where there was poor germination?

Boy, it would be great if it did have that effect on weeds. Still working on trying to find something to hold back the Bermuda grass.

Well, alfalfa lasts for several years, but it gets more sparse with age. I think a field is good for about 10 years (don't quote me on that!). But when it starts looking sad, you can't just throw out new seed. You have to plow the whole thing under and start again, otherwise you're just wasting some rather expensive seed. Stuff sets some amazing roots, too. Our neighbor re-did his field across the road from us a couple of years ago and some of the seed found it's way into some of my planters. Thought I was going to end up in China before I found the ends of those roots to get them out!

I wondered because we have 24 garden rows that we rotate and my son planted first one, then a second, then a third row, keeping the previous rows growing and just cutting it once or twice a year. After third year his plan was to plant a fourth row and plow under the first row and then keep on a regular rotation. Originally it was for improving the soil. Maybe it still is, I dunno. But I think he's gotten into other green manures and grains that he's plowed up other areas for so I think he's taking it out of the garden. Not sure. I had no idea it last for several years. Neighbor told us it wouldn't work in the south, but it has!

>> I have foolishly planted single lobelia!

Wow! Were you a surgeon in a previous lifetime? I couldn't untangle those guys if my life depended on it!

>> they benefit from crowding?

Some species! SOME! I don't know if its rare or common, but I know it's not universal.

However, the wintersowing / "Hunk Of Seedlings" folks seem to contradict what I used to think was a general rule: croiwded seedling compete with each other and never liv e up to their full potential.

Hmm, "Hunk of the Seedlings". I guess this guy left his trowel back in the longboat.

I've read that begonia seedlings like some crowding, but I don't know where I read it of course...

I've been wintersowing for years, and I plant hunks of seedlings all the time. Seems to work OK. If I have dozens, or hundreds! of one kind of seedling, I just don't worry about the possibility of losing a few. On the other hand, I would lose my sanity if I tried to separate them.

Karen

You mean that's not why they invented bamboo skewers and toothpicks?

Aah----I transplant with toothpicks too!
Petunias, Mimulus----but not Lobelia---it stays as clumps.

Remember the magnifier head band and dental curette?

Lobelia stays in clumps now! Ever try transplanting Lisianthus?

Isssss it saaaaaafe?



I think the fact that the Hunk of Seedling method works for many, many people proves an important general principle: when you read a general principle, never believe it 100%.

I've read the general principle in many places ("never plant seedlings too close together because they will choke each other out or somethin\g. You MUST thin them to the required spacing or else Bad Things Will Happen.")

But that's just not true, at least in the context of wintersowing flowers.

I'm guessing that the "Hunk of Seedlings" method would NOT work for crops like tomatoes, peppers, beans, peas, cabbage, beets, radishes and carrots.

How about lettuce and chard? Maybe they can be thinned as they grow.

Maybe the rule "you must thin" applies to crops more than flowers.

Works fine for lettuce!

Rick, when I'm working with bigger, easier seeds, I do space them and plant out individually. But with tiny seeds, like say, digitalis, I just sprinkle them in the milk jug. For plant out, I cut them into squares with a knife, and plant hunks. A few might be lost along the way, but when I have so many, so what?

I always plant tomatoes individually.

Lobelia cardinalis wintersows well. To plant out, I dig one big hole in a mostly shady out of the way spot, and transplant the whole jug full of soil intact. That first year, it just grows a nice basal rosette. In fall, I transplant the whole thing, intact again, to it's permanent spot in the yard.

I have little experience in vegetable growing. But I can tell you that root vegetables like carrots and beets need to be spaced enough that the root has space to expand and form the vegetables. And one beet seed can actually contain several beet seeds.

Karen

>> Works fine for lettuce!

Thanks! When I read that lettuce is mostly-self-pollinating, I got excited. Time to sow and save some seeds!

>> I cut them into squares with a knife,

Just last Sunday I had to move some sedum and creeping thyme I had been given a year or two ago. It had multiplied enough that I split each patch into two pots and two tiny new raised beds, and had enough left for a planter plus some scraps here and there.

I wished I had thought to bring a serrated knife with me!

I've been saving my lettuce seed. Gotta cut corners where ever! Nice thing is, you'll get tons of seeds!

I'm looking forward to "lazy sowing". No worries about spacing or germination rate or thinning. Just pour.

The thi9nning will come when I pluck or clip microgreens and baby leaf plants whole for salad.