lørdag den 3. november 2012

New shelter for cold hardy cacti.

The challenge of growing cold hardy cacti in a cold climate is often reduced to the discussion about how much frost the plants can take. But there are so much more than just the plants ultimate cold tolerance to consider when you decide what plants could be possible cultivated in your area.
The real challenge here in Denmark is not just the cold, its certainly also our damp, gray winters. Lack of sunshine and surplus of water in the form of fog, rain and rain is by far the most limiting factor. This actually goes for both our summers and winters!

For some of the most cold hardy, northern species I have developed a simple solution. A roof, made of thin plastic used for polytunnels provides the plants with a rain cover borth during the winter but also during the summer and despite the fact that the sides are open, the temperature in the summer are raised a few degrees, enough to provide the plants with much better conditions. The perfect ventilation also reduces the risk for any evil fungus attack, an otherwise common cause of cactusdeath here.

The plants chosen for this project are mainly very northern species of opuntioids from Canada, northern US states, pediocacti and some Escobaria vivipara forms. Also forms of Echinocereus from Kansas, Oklahoma and Colorado are tested here.

Very simple setup!

Opuntia fragilis from Illinois.
Opuntia fragilis from Minnesota.

lørdag den 20. oktober 2012

Yucca filamentosa 'Rigmor'

Variegated plants are often valued by gardeners and rare forms are sold to high prices. With some plant generas breeding for new variegated forms is easy like with Hostas. For other families only one in a million or at least one out of 1000 seedlings shows the wanted variegation.

Within the genus Yucca serverel variegated forms are known. 'Color Guard' and 'Golden Sword' being among the most common and these are easy, cold hardy plants. Another plants often sold in garden centers is Yucca gloriosa variegata. Showing lots of variegation the plant is not particular cold hardy and it dislikes both our summer and winters here in Scandinavia, both being too cold, too wet and the winter too long.

Some years ago I sowed a handful of seeds from a Yucca filamentosa collected in Connecticut. 3 plants germinated, one being with green yellow leafs and one showing variegation.

One of the yellow, green Y. filamentosas from Connecticut.
The flowers were yellowish and bell shaped.

Yucca filamentosa 'Rigmor'.
It does share similarities to Yucca gloriosa variegata but is much more hardy to both cold and rain. I decided to name it after my daughter Rigmor.

The flowers were very different from the other clones wíth almost pure white flowers. So far I have not distributed the plant as it is a very slower grower.

fredag den 19. oktober 2012

More carnivorous plants...

Its really getting colder now and all the plant action from 2012 has ended. Sarracenias is really a highlight of the summer as most of them wont start growing until end May or even mid June. These are pictures frpm July.

Sarracenia x (catesbaei x purpurea).
Another purpurea-hybrid.
Sarracenia flava maxima from Virginia.
Sarracenia oreophila.

Carnivorous Plants 2012

This year has been a real succes when it comes to the carnivorous plants in the garden. Despite a really cold winter with temperatures on serverel occations down to minus 24C and even colder for a few hours, all the plants survived outside. Now around 300 different carnivorous plants grow healthy in our danish Z6 garden. Here is a few examples - much more to come:

Sarracenia (purpurea venosa x catesbaei) x oreophila.
Sarracenia courti x purpurea.
Sarracenia x catesbaei in bronce.
Yellow Sarracenia x catesbaei from a locality with naturalised pitcherplants in Denmark.
Sarracenia leucophylla hybrid.
Another leucophylla hybrid. Leucophyllas are not hardy outside as our summers are too cold, but mixing them up with S. purpurea genes sure helps.
Here is another Sarracenia from the danish locality. Here the purpurea genes are obvious.
Of pure species Sarracenia purpurea purpurea forms, oreophila and flavas are the best. But mixing their genes with more tender species certainly improves the selections of what can be grown outside. 

torsdag den 18. oktober 2012

Gladiolus dalenii

As a surprise this spring, Gladiolus dalenii proved hardy in our past winter despite of a low of minus 24C. Growing not too far from the house they experienced some sheltered and were not too wet in winter, but still, they are from Africa. They flowered for serverel weeks in July. The plants are from wild collected seeds and showed some variation.

torsdag den 4. august 2011

Drosanthemum speciosum

Drosanthemums are underused plants. Even for gardeners in a temperate climate they are excellent for use in large claypots on the patio. They are not hardy as many Delospermas and here up north the real challenge in growing them is to get them through the winter. The best position is a bright, cold but not frosty position with relatively dry air.

After winter they can come outside when there is no risk for hard frost. The good news is that a cold, dry night with temps down to - 4C does not harm them at all as long as day temperatures are above the freezing point. They dislike the combination of rain followed by frost.

They need plenty of water all summer and starts flowering end June, early July.

onsdag den 27. juli 2011

Delosperma as weeds...

Some forms of Delospermas are simply weedy. They are not as plants particular cold/wet hardy, but their seeds are and they germinate everywhere! One example is Delosperma cooperi. And all its hybrids or forms. The plant shown on the picture may in fact not be the real thing. This one behaves very well.

Other forms grows like maniacs and a seed can turn into a 1 squaremeter of a plant producing a zillion seeds. I even have them germinating and growing, if I led them, in my garden bog. In wet, peathy soil!

Another weed is Delosperma herbeum. Also not really cold hardy, but the seeds are. It does, however, grows the best inside the unheated greenhouse. It likes the heat.

When you grow plants, closely related to each other, often hybrids are produced. This next plant germinated this spring. Not Delosperma herbeum. Not Delosperma floribundum, but something in betwin...

Note the waterfilled leaves. We simply have had too much water this year...