Feeding and repotting Hepatica japonica cultivars

[Rodger Whitlock]

Having acquired several of the Japanese doubles last week, I am naturally interested in giving them the best possible care: too expensive to replace if lost!

I've carefully combed the SRGC forums for information, but one important datum has escaped me: what, when, and how much to feed these beautiful plants. Ian Christie in his Nursery Workshop screed uses JI composts as the base for his hepatica mixture, and all the JI composts contain fertilizer, but what else has been found to work well? I note a side reference to monthly feedings with "liquid", presumably a weak solution of some soluble fertililzer.

There also seem to be differences of opinion about when to repot hepaticas. "Repot in July" is the advice, but there is also the advice to propagate by division in the fall. it seems to me that the optimum time for division would coincide with the optimum time to repot.

[ichristie]

Hi Rodger, I use a basic tomatoe or general liquid fertiliser at around half strength once a week when in full leaf, I also divide as you suggest when we are about to pot and i usually wait until the seed is ripe so we can collect it but I did divide some plants last week as it is nice and cool at the moment. I have also started to add some beech leafmould to the compost wonderful if you can get it, cheers ian the Christie kind.

[Gerry Webster]

I'm no expert on Hepatica but I grow a few - inexpensive single forms - & manage to flower them regularly & reasonably well. Plants seem to produce new roots sometime between the production of new leaves & flowering coming to an end. It would seem sensible to divide them at this time.  My plants are fed  with half-strength Phostrogen (10:10:27 + trace elements) at weekly intervals.

[Ewelina Wajgert]

We repot and divide Hepaticas always in July. By repoting we give to the soil some Osmocote. Then the Hepaticas have time to rooted before winter.
But I know person, that divide Hepaticas later (in October). I think they are then poor, in order to flower beautiful in spring.

[Rodger Whitlock]

More on hepatica potting composts. At http://www.hepatica.eu/growing.htm, two soil mixes are suggested for Hepatica japonica. It took some cyber-sleuthing to identify the various ingredients, so I will give a precis of my findings here:

• kanuma is pale yellow, weathered pumice emitted from the Mt. Asama volcano, pH5.6-6.4.
• akadama is a volcanic (pumiceous, presumably) soil from Mt. Fuji, pH 6.5-6.8.
• towada and karuishi are light sand w. micro holes, also presumably pumiceous.
• "burnt crey" may be a misspelling for "burnt clay"

The thing I find remarkable about these mixes is that they are entirely mineral with no organic matter at all.

Has anyone reading used such a soil mix for their precious hepaticas? If so, what results did you have?

[Joakim B]

One thing to remember is that the summers in some part of Japan is very warm and humid up to 40C and when growing here one needs special mixes to prevent rot or fungus to get hold of the plant. I do not think that the hepaticas grow under such conditions naturally, but I may be wrong.
The European site probably only refere to the Japanese formula.
Some of these ingredients can be found at stores that sell bonsais.
I think that most European growers have well drained mixes but with organic content but hopefully they will tell You more.
Hope You here from many if they do or if they do not use organics in the compost.

Kind regards
Joakim

[ichristie]

Hi again, I have never used any of these ingrediants but one very important thing is never bury the growing noses and watch very carefully when you water, cheers ian the Christie kind.

[Rodger Whitlock]

. . . the summers in some part of Japan is very warm and humid up to 40C and when growing here one needs special mixes to prevent rot or fungus to get hold of the plant. I do not think that the hepaticas grow under such conditions naturally, but I may be wrong.

I think you are right, Joakim. This reminds me of a little-known principle: the composition of an appropriate potting compost depends on the climate, and, yes, these all-mineral (actually, all-pumice) mixtures are a response to Japan's hot, wet summers.

I use pumice freely in my potting mixtures, but pure pumice is reserved for tricky plants: Weldenia candida, Nierembergia (Petunia) patagonica, and such. Pumice is ideal for such plants because, while water-retentive, it ensures very well aerated conditions at the root.

But given that the climate here has a precipitation regime precisely the reverse of Japan's (we have wet winters and dry summers, they have wet summers and dry winters), it would be fully (recte, "folly") to risk precious double hepaticas in such a mix here.

I am pretty sure that Hepatica japonica will do better with protection from winter wet, so it will be a cold frame or bench with overhead cover for these treasures.

[Diane Whitehead]

I have my hepaticas, including a semi-double Japanese one, Aofuku,
growing outside. 

The singles don't get any attention, but I cover Aofuku with a glass
cheese dome for the winter so it doesn't get rained on too much, and
make sure to water it often in the summer.

[Afloden]

Roger,

 A friend in Japan sent me some sample of each of these sands and the turface (fired clay) and I tried my best to make something similar with what is available to me in east TN and when I was in KS. I used heat expanded slate, turface, a builders sand and had awful results. I then changed it and added some composted pine bark and failed nearly as bad. So I went to my regular potting mix with turface at about 50% and did better. Last summer I put most of them in the garden and have had no losses, so I am giving up pot grown Hepatica. I lose most of them in the winter and I am not sure why.

 My friend in Japan grows all his in the sand mixture with dilute weekly feedings and grows several hundred seedlings each year (all on an apartment balcony!). They are given no direct sun in the summer, and starting in the fall exposed to more and more sunlight so the flower buds develop fully.

 Here is an H. americana flower from the only population I have ever seen where the pistils are reddish. And another americana with beautiful leaves.

 Aaron Floden
 Knoxville, TN

 

[Paul T]

Nice leaves!!

[Rodger Whitlock]

A friend in Japan sent me some sample of each of these sands and the turface (fired clay) and I tried my best to make something similar with what is available to me in east TN and when I was in KS.

Clearly, what both Tennessee and Kansas need are good volcanic eruptions to supply the gardeners with pumice!