Saturday, 1 September 2012

6. Sowing Lithops Seeds




I prefer to sow in spring and start seedlings off with the same substrate I use for adult plants (2). To prevent it falling through the drainage holes I put a little piece of shade cloth in the bottom of the pot (1). Good results can be obtained by filling the top 5 - 10mm of the pot with fine silica sand and then sowing seeds onto that (3 - 6). After sowing I cover the seeds with a thin layer of medium sand. This allows the roots to anchor themselves quickly and easily. The seedlings stay upright supported between the medium sized sand particles. If you sow directly onto the substrate, a portion of the seeds will land on gravel particles or pieces of bark and for a Lithops seed which is so small it’s hardly visible that’s the equivalent of being stranded on a large rock. If it does germinate it will battle to anchor itself and grow.

Pour the seeds out onto a piece of folded paper (5) so that they can be drawn out into a line and swept off the paper into the pot, using a fine paintbrush. Since my space is limited I like to space seeds individually. It’s a painstaking job especially for a species like L. olivacea which has really tiny seeds but I find it worth the effort. The pot pictured is 8cm in diameter and seeds are spaced so that seedlings can reach a size of at least 5 - 6mm in diameter before they need to be transplanted. Once the seeds are in position I spray them lightly (7) just to get them stuck in place so that they don’t move around when I cover them with the medium sand (8, 9). As a precaution I apply a fungicide once after sowing. Lithops seedlings are the only thing on which I use preventative spraying and this is also the only time I will use a fungicide on Lithops.

Seeds should not be allowed to dry out until germination is complete. I spray them once a day and allow about 14 days before reducing the watering frequency. Sometimes the first tiny plants can be seen within 2 – 4 days.

1. Pot (8cm) with a piece of shade cloth to prevent substrate falling through the drainage holes.


2. Almost fill the pot with substrate. Leave the top 5 – 10mm for fine sand.
3. Top up with fine sand and level the surface. The back of a saw blade works nicely.
4. Some marks on the surface will help to space seeds evenly. The saw blade is handy again.
 

5. Pour seeds onto a piece of folded paper.
6. Position seeds on the surface using a fine paintbrush to sweep them off the paper one by one.
7. Gently spray the surface to fix seeds in place.


8. Carefully cover with a thin layer of medium sand.
9. Water without disturbing the surface.


10. L aucampiae 38 days (left), L. salicola 29 days (right), L. otzeniana 29 days (bottom)

11. L aucampiae 127 days (left), L. salicola 118 days (right), L. otzeniana 118 days (bottom)

17 comments:

  1. Hi P, Great post! Excellent photos! Nice brush. ;) Photo 6 is a work of art! You are Amazing!!

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  2. Hehe... thanks :) Those are L. hookeri seeds, which together with L. lesliei and L. aucampiae are simply gargantian compared to some other species. So that one was easy - the other pots don't all exactly conform to the standard model... I'll follow that pot and post some pics as they grow. They'd better grow!

    The brush is just a cheapy from the stationery shop. I don't think they had to pluck any animal for it... it's probably nylon or something - but the sharp point makes it work quite nicely.
    :-)

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    1. I've read elsewhere that once Lithops seeds are sowed, they should not be covered because they need sunlight to germinate. Is this partially true? :)

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    2. That's a good question. I've heard that apparently the seeds require light to germinate but haven't really looked into it. I am fairly certain that the silica sand I use allows light to reach the seeds. The layer on top is thin, there are sizeable spaces betweeen the particles and I grow outside in very, very bright conditions. So if they do require light they are probably getting enough. It has happened that when repotting I discovered a plant which wasn't there before 8-0 - one that has grown just below the surface of the sand for more than a year. However, if you grow indoors and cover seeds with a completely opaque material I'm sure it's a different story.

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    3. BTW. And - as I think you've also found, having something to keep the seedlings upright and supported is quite important. It's a nightmare to find your precious seedlings lying flat on seedbed with their roots in the air like a fish out of water. It then requires the most delicate of surgery to get them into position again and you're almost guaranteed to injur them. In the process you end up disturbing the other seedlings too. So I'm not very keen on leaving them uncovered.

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    4. Eeeek!! I've just sowed my new seedlings and have covered them with a thin layer of small pumice, which is opaque compared to sand, so am worried that I might have given them a burial even before they've sprouted. It's been four days and I still haven't seen one sprout. :( Yes, I agree that its wise to cover the seeds to give the seedlings support when they grow, but I think that medium sand might be the better choice for this, or maybe I should sprinkle the support material after they've sprouted/grown a bit. After you've covered them with the medium sand, where do you put the pots? Seeing that you've filled the pots to the top with sand, how do you seal/shelter them, ie: do you use glasshouse/plastic bag or perspex etc to assist with germination?

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    5. Hmmm. I'm not sure that light is in fact necessary, only that mine do get light. I wouldn't panic yet... Rika also sows directly into pumice (not sure whether she covers them or not).

      Mine go onto the lithops table, which has a sheet of glass and frost cover over it. It's not sealed - that would be a solar heater :) The sides are open but it keeps the rain / hail / birds / sunburn at bay. http://lithopsandthings.blogspot.com/2012/05/setup.html & http://lithopsandthings.blogspot.com/2012/05/setup.html

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    6. Ohh yes of course now I remember. Rika doesn't cover her seeds with extra pumice, just a perspex over the pot I think. You don't think humidity is important to germination?

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    7. I think it's important that the seeds and germinating seedlings don't dry out. The fine sand remains wet for quite a while because water is atrracted with surface tension and there is the layer of covering sand. So seeds stay wet enough under my conditions if I spray them once a day. If you sow directly onto pumice - which is presumably quite a bit more coarse than the fine sand, the water relations are quite different. Then I would seal with a bag or piece of perspex or whatever. Obviously you can't keep that in the sun as it will cook in no time at all. I suspect that if you sow seeds onto fine sand, press them down lightly with something flat and then spray them daily, without covering, they will also germinate, given the adaptation of Lithops to very dry conditions and their almost immediate response to even the smallest amount of water :)

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  3. Can't get any better than that....instructions and pictures!! Great idea for a post! I've sowed Lithops a few times, without the best results. This inspires me to give it another go and tweek my strategy a bit. Thanks!

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  4. Thanks Arid. Yip - do give it another go with seeds. It's a wonderful way to expand one's collection and scouring the seedbed for new and unusaul things makes for great excitement :) Nevermind - my first attempts were pretty disastrous too, but once you understand their needs they're actually quite easy.

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  5. Thanx a lot for this very clear "lesson" :) Best regards, Marc.

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  6. Great. I'm glad if it's useful :-)

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  7. Ok, man, one question: after this gentle moisturising, when is the next time? Depends of the weather or the phase of the Lithops?
    Thank you for the exhaustive article, is amazing!

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    1. Yes, it does depend on conditions and the growing medium. Newly germinated seedlings should never dry out. Nowadays I am growing in pure LECA - then newly germinated seedlings can be watered daily. If you use soil or a soil mixture you can water every couple of days because soil holds more water. Young plants can take more water than adults.

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    2. Thank you very, very much! And one last thing: I will re-pot my Lithops in next few days in a succulent mix + sand and different sizes of stones.... I am very worried about the organic part: is it possible to miss it? Because here in Bulgaria we have four seasons and i should to insure the quckest way to dry.

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    3. Yes, the organic part can be left out. Rika in Germany grows in pure pumice. http://lithops-stories.blogspot.co.za/

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