Welwitschia mirabilis

[Karsty]

Hiya Folks,

I am trying to grow the extremely weird Welwitschia mirabilis from seed which normally resides in the Namib Desert.

The question is, As this plant is neither cactus nor succulent, nor even xerophytic, is this forum the right place for it?

Karsty.

[Karsty]

Ok, Yes it has just occurred to me to do a search to see if this plant has already been discussed here, and I see it has!

There is so much contradictory information about growing this plant, and so much uncertainty, so I will post my experiences here.

Firstly, about 20 years ago I grew some successfully from seed, but killed them by letting them dry out.

I read some advice saying you should remove the seed coat before sowing. I have done this this time around, and out of 20 seeds I found 10 were already dead. So that was good advice.

A couple of months ago I tried growing a few others. I removed the seed coats (found some were dead), and soaked them all in fungicide overnight. Most did not germinate, and the couple that did died before even showing cotyledons. I had planted them in a very sandy gritty mixture with some mixed acid leafmould.

This newest batch are planted in a mixture recommended here, about half way down: http://florawww.eeb.uconn.edu/reference ... ilis01.htm

I used mainly quartzite grit and sieved quartzite sand (to remove the finer particles) and also a bit of crushed charcoal granules. I left them in unheated propagators high up in a south-west facing conservatory. So far I can confirm 9 of the 10 seeds have germinated. One grew cotyledons then died (it could have dried out). 8 are showing healthy above ground. One has germinated but not yet showing above ground. I planted them in the mixture covered by 5-7mm of the same mixture. They needed daily attention to get the watering right. I raised the covers once I saw germination, and after a couple of days removed them entirely.

I shall post some pictures this weekend.

Karsty.

[Aiko]

Some things to know about Welwitschias, although I can imagine the first one is more a myth than actually true. There is an article online somewhere (translated in bad English from Swedish via an automatic translator) that dismisses the need for big pots. But when I sowed mine I stuck to big pots anyway:
- They seem not to like repotting a lot in their first few years. So it is adviced to sow them in big (tall) pots so you don't have to repot them anytime soon.
- The are not succulent, so do need to have very regular waterings. I give mine a big splash every week (unless the soil is still moist). Tall pots help to control the plants not to dry out too much. I have about two centimeters of space between the soil and the edge of the rim. So I just pour water until it overflows, and allow that to sink into the soil. That is usually enough for one full week in a hot burning very sunny greenhouse my plants are in.

These advices probably correspond with the link you gave. It worked for me. But yes, there are always seeds that don't germinate. And occasionally a seedlings suddenly tumbles over and dies soon after. I consider that to be 'normal'.

[Karsty]

Thanks Aiko,

I have just read something saying the soils in the foggy zone where Welwitschia lives are brackish. Should we now be putting extra salts into our Welwitschia pots?

It's true, the photos of Welwitschia in habitat show it growing in sand/grit/gravel (I think I will pot mine up in 100% mineral soil).

Just read some other info about Welwitschia, trying to piece it all together...

It grows in the foggy zone and for 50km beyond it. In this area the humidity is, however, up to 50%

The brackish soil is in the foggy zone only. So it lives in brackish and non-brackish ground.

Some areas are calcareous, and some areas are also gypsum.

So, I will try zero organics, a little tufa and gypsum, pumice, and quartzite grit/sand.

And looking at the temperature records, almost anything above freezing will be good.

[Karsty]

Ok,

I have just received and peeled another 20 seeds. 10 of them were dead, exactly like last time. That's ok, they were relatively cheap. and in fact it's a good number for the space I have.

An interesting thing has happened. In the last batch of 10 living seeds I got 100% germination. 5 of them were simply sown in the media, and the other 5 were sown on a pinch of mycorrhizal inoculant - TNC MycorrMax - which also includes some bacteria.

Up to this point, 5 out of 5 sown plain in the media have died i.e. all of them. They just went rotten underground and keeled over. 4 out of 5 of those inoculated with TNC MycorrMax are still alive. How about that? Is that not flipping interesting?

I kept the last 3 dead seedlings to investigate them. They had a fine white mycelium growing over the seed, with small black fruiting bodies, globular but not smooth, like lots of smaller black spheres stuck roughly together.

Also, the root and shoot both emerged from the point at the blunt end of the seed, seemingly not fussy about orientation. However, I tried several times letting the seeds drop to the floor, and also blowing them about a bit to see how they end up. Most seemed to end up lying flat side down, which makes sense if you think of them falling them blowing about.

So, the theory is, the beneficial inoculant takes the place of pathogens and prevents them from infecting the seed.

This time I will plant them under 5 - 10mm of potting grit. I'm wondering if I should use the inoculant on all of them?

Karsty.

[greenknight]

The inoculant you used contains Trichoderma, which attacks other fungi. If it prevented pathogenic fungi from attacking the seedlings, that's not surprising - it's exactly the purpose of inoculating with it. I would keep using the inoculant.

[BarryRice]

We grow them at UCD regularly. No special treatment. They're quite easy.

Never, ever, ever let them dry out.

[Karsty]

Phew, made it back at last!

I'm going to post some photos of what I've done with the 10 live seeds, well, 9 of them to be precise.

They are in a mix of quartzite sand, pumice, a little charcoal, gypsum from plaster of paris, quartzite grit. They are in white plastic pots approx 50mm wide and 90mm deep, which I "made" myself from plastic bottles. I bought a variety of man-made-fibre cords to test as wicks, and a black flat nylon paracord came out heaps on top, second was strips of Aquamat capillary matting. So I first put the wick inside the drainage hole then filled up each pot. Then they were planted with the TNC MycorrMax inoculant below and above them. Under about 7mm of the same mixture. I didn't want to use pure grit as then I couldn't easily tell if they were drying out.

Then they were all placed into carefully chosen "saucers" that I got off ebay the were just the right fit, the wick was wound up inside these saucers. Then carefully chosen clear plastic bottles were placed on each. The whole set up was designed to be self-sufficient with water.

Incidentally, I microwaved the mixture first, and used boiled rainwater to water them!

Then I set it all up on a thermostatically controlled heating pad for 29°C during the day, and switched off at night (room temperature).

The first seedling appeared on day 8, and the sixth on day 12. Three are still non-showers.

As soon as I saw them, I took them out of the propagation set up, into full SW facing sun.

The IMG numbers with each photo show the exact date and second they were taken.

Still more pics to follow this.

Karsty.

[kristian_Fossmo]

God germination! Interesting plants indeed. I think the later two of mine is gona make it also so I have three growing strong now.

[Karsty]

I've got 3 all in one pot now, they had the mycorrhiza treatment, now they are green and just starting to grow, I think they have passed the danger period.

I seems to me that if you don't get germination within 2 weeks, they will not show themselves.

Kristian, will you post pictures of your plants? It would be great to see them

[kristian_Fossmo]

I have some pics of them in my grown from seed thread: viewtopic.php?f=16&t=35150&start=90" onclick="window.open(this.href);return false;, on page 7

[Karsty]

A piece of information - according to the seeds I have grown recently, you can reckon on about 25% germinating and surviving. When you peel them, you find half of them are dead. Then about half of those left either fail to germinate, or they germinate then succumb to mortality.

[kristian_Fossmo]

Are they wild collected seeds, or from grown plants?

[Karsty]

It has been a bit hard to find out, but I am pretty sure they are wild collected seed. They are from a German supplier - http://www.exot-nutz-zier.de/

I read that the wild collected seed which are infected with fungus are blackened, and will not germinate at all.

[Karsty]

I had one odd seed left, so I planted it in the middle of the pot with three planted together already, and within a week it has germinated. Just English autumn room temperatures.