Friday, 21 September 2012

7. Progress Pictures

These are just some recent pictures, a state of the nation update from the Lithops patch.

A reddish maroon L. aucampiae from Francois Hoes.

L. gracilidelineata
L. julii from Francois Hoes. Two are reminiscent of that kiku... whatsa name sort.

L. julii with nice reticulated pattern.

L. karasmontana from Francois Hoes
L. karasmontana from Francois Hoes

L. karasmontana from Francois Hoes

L. lesliei. A purplish one too – yipee! Frieda’s purple rinse?
L. salicola. A wine god red one from Francois Hoes.

Adult of mysterious parentage from garden centre. L. aucampiae me thinks.

Also of suspicious lineage. I think L. lesliei.  It has very faint peachy undertones. Interesting.
L. karasmontana. Nice reddish ones from Francois Hoes.

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)

Tuesday, 31 July 2012

5. Watering Lithops

This is my take on how / how much / how often to water Lithops.

The most important thing is to understand the growth cycle of Lithops. Lithops grow in a cycle which has identifiable stages; young leaves grow and expand and then flowering occurs. After flowering the mature leaves shrivel while new leaves are formed. In order to facilitate this process in cultivation, it is advisable to water during certain growth stages and to withhold water at a certain stage. Fern growers brace yourselves: Lithops should remain dry (NO watering) for the period starting after flowering, while the old leaves shrivel and dry out and the new leaves emerge. This usually takes a number of months and during this time the plant is able to use reserves in the old leaves to generate new leaves. In cultivation, it is practical for plants to go through this stage in winter. The substrate should remain fairly dry during this period - it's no use having a substrate which stays wet for 3 months after watering! If that’s the case, the old leaves probably won’t shrivel and dry as new leaves emerge. More importantly, the plant might unceremoniously rot and die! Once new leaves have emerged and the old leaves have shrivelled and dried completely, watering can start again. In cultivation, this should usually be around spring or summer.

For Lithops to thrive, the substrate should dry out fairly quickly (a few days at most) after watering. One grower’s plants reside indoors on a windowsill in Germany and grow very well in a 100% pumice substrate. Under such conditions (northern hemisphere, indoors) a substrate should have minimal water retaining capacity. If for example you grow outdoors in a very hot, very bright environment with generally low humidity, like I do in South Africa, you can achieve good results with a substrate which holds more water for longer. This is the mixture I use. Plants grown in a pure pumice substrate or something similar will require more feeding than plants grown in a substrate which contains soil and / or organic matter.

If the plant is an established adult and has completed a year of good growth in a substrate appropriate for the conditions, a drench which wets all the substrate in the pot thouroughly should be in order once old leaves have shrivelled and dried and new leaves have emerged.

Lithops which are plump and firm or swollen have had enough water and only need to be watered again once they start to shrink a bit. Small lines or wrinkles may appear which indicate that the plant is losing water and is starting to shrink. How often you water will depend on your conditions (light, temperature and humidity). I can only speak for my conditions and in the hottest part of summer in South Africa, using the substrate above, I might water once or twice a month. You’ll have to experiment a bit - but wait for the plant to show signs of shrinking before watering.

To summarise, water during spring and summer, only when plants show signs of shrinking and stop watering after flowering, in autumn or winter, so that plants are able to complete the replacement of old leaves with new ones. Resume watering in spring / summer once the old leaves have completely shrivelled and dried out and new leaves have emerged.

If you have a new plant which isn’t well established you may need to be more careful. If you don’t know what conditions it came out of it could be at any stage in the growth cycle. It may have grown for a whole season and want to flower and start replacing its leaves or it may have just replaced its old leaves with new ones. It may be somewhere in between. You'll have to look at it, try to figure out where it is in its growth cycle and then do your best to get it synchronised with your seasons. If you have conditions which are not optimal, I imagine it would be a good idea to get new plants only around spring. If they start to shrink, water, if they're not shrinking, don't. If you get new plants in winter, withhold water as far as possible in order to promote shrivelling of the old leaves and formation of new ones. There is some guessing involved with new plants.

Regarding seeds & seedlings - Seeds need to be regularly watered to germinate. I put some substrate in a pot, cover the top with about 1cm of fine silica sand and sow the seeds onto that. I cover them with a THIN layer of medium silica sand and then water by spraying once a day so that the surface isn't disturbed. Once germination is complete, (usually after about 2 weeks) the watering frequency should be reduced. It will only be necessary to water when the substrate begins to dry out at root level. Stick your finger in to check if you have to. I recommend sowing in spring or early summer. Watch the seedlings carefully and you'll be able to see if they show signs of shrinking. That's a sign that they need water (unless it's a case of damping off and they're disintegrating). In addition, depending on your conditions, you'll see that seedlings can form new pairs of leaves more than just once a year. Under my conditions, they can make 3 - 4 pairs of leaves a year. Once they are full grown, they begin to form only 1 new set of leaves every year.

If you use a sealed container to germinate seeds, watering will only be necessary once after sowing and then again only some time after you've opened the container and the substrate has started to dry out. I don't think it matters much whether you water from the top, from the bottom or by spraying – as long as the tiny plants are not disturbed. Remember that salts tend to build up in the substrate of pot plants which are not flushed from time to time with plain water. It will happen to a greater extent with plants which are watered from the bottom or fertilised often.

Sunday, 17 June 2012

4. Promising Seedlings

These are some more seedlings - ones which I think are worth keeping an eye on for future selection. To my mind (in daylight and if you look closely...) they show some rather pretty colouring. Some seedlings don't have their first true leaves yet which is an indication of their real size. They're still tiny! Anyhow - here they are:

 L. comptonii
 L. hallii
 L. hookeri
L. comptonii  -  Mesa Gardens 1563.2. I think there's great red, blue and green potential there.
L. hallii - salicola reticulata grey C087a from Francois Hoes. At 0, 20 & 40 minutes I spot some teal, at 25 and 35 minutes, blue.

L. hookeri - v. marginata cerise C087a from Francois Hoes.  I think the one in the centre has a nice orange colour evenly distributed throughout.
 L. verruculosa
 L. dorotheae
 L. gracilidelineata
L. verruculosa -  glabra C160 from Francois Hoes. Here I see blue, green & pink possibilities.
L. dorotheae  - C300 from Francois Hoes. Lovely as always. Greenish, pinkish and a sort of tan one besides the more standard yellow & red one. Should present good opportunities.

L. gracilidelineata - C309. One is pinky & yellow and more spotted than the rest. Could be interesting...
 L. karasmontana
 L. verruculosa
 L. verruculosa
L. karasmontana - lericheana C330 from Francois Hoes. I'm the most excited about these. The three in the centre (most obvious on the one on the right hand side) have wonderful purple stripes which are absent on most of the others. Orange with purple stripes... Now you're talking! (My taste has always tended towards the gawdy).

L. verruculosa – inae from Succseed. I like the variation from brownish to bluish and the one at 45 mins has almost clear aucampiae-like windows.
L. verruculosa - Rose of Texas from Francois Hoes. A nice blue stripe on the side. Yum.

Feline child aka Katastrofes
L. otzeniana - 'Aquamarine' The vibrant green of the new leaves is too lovely.

Feline child on the Lithops table

Thursday, 7 June 2012

3. Lithops Potting Mix

I think Lithops do well in a potting mixture which is largely sandy and very well drained. Water should run through it freely without forming a dam in the pot and it should not stay wet for days on end. However, there should be a small percentage of smaller particles in the mixture or it may happen (especially when repotting / transplanting) that the roots end up hanging in an air pocket without making sufficient contact with the soil. You find that even after repeated watering the plant just doesn’t take off. The roots need to make proper contact with the soil and having too many large air filled spaces makes this difficult.

I use (by volume):
*1 part washed small gravel
1 part washed medium sand
3 parts washed fine sand. It should flow freely and not resemble talcum powder.
1 part coco peat / coir or peat moss
1 part potting “soil” which is in fact well composted bark
1 part unwashed gravel (probably contains about 5% soil)
0.5 parts sandy soil.




When combined the mixture consists of roughly:
35% non absorbent stone
35% sand
24% organic material
6% sandy soil
(by volume)

That should enable the mixture to provide adequate moisture without becoming waterlogged and staying wet for long periods. It should feel coarse and gritty and should not form a ball when squeezed. I add about 1 teaspoon of dolomite lime to about 5 litres of the mixture to provide calcium for strong teeth and bones and magnesium for bright eyes and a bushy tail. Whether they grow because of it or in spite of it I can’t say.

Keep in mind that I grow outdoors in a bright, hot southern hemisphere climate. Indoors one may need to slightly increase the quantities of non absorbent stone and decrease the amount of soil in the mixture because it may not dry out as fast. It will always involve some trial and error.

Enjoy planting!

Update 26 June 2012
I've increased the amount of washed small gravel to 2 parts.