A. japonicum 'Fairy Lights', Fall 2017, Love the spectra of yellow, orange, pink and red on this little tree. In container. In full soon. No shade at all. A Very tough little tree.

'Fairy Lights' in spring 2017 (plant on the left, next to a red A. palmatum 'Aratama')

Aratama in Fall 2017. Also in full sun. It loves the location. Fall color ranges yellow to orange to red.

A. palmatum 'Kamagata'. Fall 2017. Also grow in full sun and no fuss at all.

I need to start taking pics of mine! here is all I got, a pile of leaves after I defoliated my Shishi Yatsabusa. I love how tiny the leaves are!

Nice cute tiny leaves for Shishi Yatsabusa. Love the spectra of colors they have! Do you have it planted in ground? Thanks for sharing.

Lovely trees, Vivian. Can you give me some advice on soil mix and winter care for potted maples? My lust for JMs reaches beyond the possibilities of my yard, so I am thinking of giving pots a try.

mblan13, I am putting Shishi Yatsabusa on my wish list. I need trees that stay small since all mine seem to grow faster than expected in containers even though some of them were labeled slow growing.

Mens Tortuosa: Thanks. I am no expert in growing JMs in containers even though I am a long time gardener. The container gardening forum and this forum have tons of information, which I learned a lot from. What is described below seem to work for me very well for the last 2 years.

I am growing 17 different japanese maples in pots (small yard, 10 JMs in ground, many conifers and a weimaraner who needs a large grassy area to run). For containerized ones, they are mostly from online sources ( 1 to 3 gallons). majority of them are dwarf ones. I potted them up in containers ranging from 3 to 7 gallon.

I travel frequently for work so low maintenance is a must. I also intend to have these trees in containers for as long as they live. So they may need to be repotted and root pruned once every few years.

1. Make sure potting soil has good drainage. I mix potting soil with small pine barks (~1/4" size), 1:1 ratio. You can also use small mulch barks (or reptile barks which come in perfect size ~ 1/4") or soil conditioners (use the ones made from pine barks). Experts from the container forum recommend 511 mixture or gritty mixture. Recent thread there has tons of good information. But these mixtures require more frequent watering so I decided to stay with the 1:1 ratio. http://forums2.gardenweb.com/discussions/4910399/turning-potting-mix-into-5-1-1?n=60

2. after the tree is planted in the container, add ~ 1 inch of mulch (or pebbles) on top of the soil, to prevent moisture from evaporating thus significantly reduce the need for watering. I only need to water ~ once a week during the summer when there was no rain for multiple days. Use the finger check trick if not sure (stick finger into the soil under the mulch, it it is moist, no water).

3. Leave the containers where they can benefit from rain (for example not under heavy canopy of trees).

4. In the spring, Spread ~ 1-2 tbs slow release fertilizer (miracle grow etc) on the surface. That should provide the nutrients for the rest of the season.

5. I winterize them in attached unheated garage. All of the containerized maples survived and are growing really well. I leave the containers outside until the night temp consistently drops to below 25F, then bring them into the garage (~ late Nov or early Dec in Chicago area). Experts in this forum say that best temp for JMs to stay dormant is 25-45F. My garage, temp never drops below 20F, but sometimes they can be above 45F for several days in a row. When that happens, I open the garage door at night for a couple of hrs. Only water them lightly once every 5-6 week so they don't dry out.

6. The trees in the garage do wake up 2-3 weeks earlier than ones in ground. Once new leaves start to unfurl (around late March to early April for me), I bring them outside, but close to the garage. When night temp predicted to drop below 32F, I bring them back to the garage at night. This happened a few times last couple years. For this reason, I typically plant the trees in plastic nursery pots for ease of handling. You can put them in decorative ceramic or plastic containers.

6. I also winterize a few potted JMs by burying them in ground, pile a few inches of leaves and mulches. This method works out so far.

Hope this helps.

Vivian, beautiful trees! thanks for sharing. May I ask what potting soil you use to mix with the pine bark?

Stuart, I use the potting soil from a local upscale garden center's own brand: Pasquesi. Their brand is formulated for general purpose. Potting soil from any good garden centers will be fine.

Vivian

Mens Tortuosa, I use and recommend Gritty mix:

1 part Pine Bark (screened to 1/8 to 3/8 inch),

1 part turface/optisorb/NAPA 8822 (bug screened to remove fines)

1 part Grani-grit Grower size (from farm feed stores, bug screened)

It works great and will last about 5 years before you need to root prune/ repot, but the granite makes it quite heavy if you use 10-25 gallon containers. I'm thinking I'm going to sub pumice or haydite for the granite to make it a bit lighter.

Or 5-1-1:

5 parts composted Pine bark (soil conditioner)

1 part spaghnum peat moss

1 part pearlite.

It's much lighter, but you'll will need to replace soil every 2-3 years.

I use DynaGrow foliage pro liquid fertilizer at half strength twice a week and plain water with white vinegar or sulfuric acid to get to a 5.75-6.25 pH

I will echo mblan13's recommendation for the gritty mix. I also use a modified 5-1-1 for some of my containerized maples as well. Whatever you choose, you do NOT want a standard commercial all-purpose potting soil (peat or coir based) but a very textural bark based mix (which are very difficult to find commercially). This will provide the fast drainage required with a minimal PWT (perched water table) and significantly reduce any concerns about root rots as well as the need to repot and refresh annually.

Gardengal, what's your modified 5 1 1?

Thank you all for sharing your experience. That is how we learn:)

For me, I had to find a potting mix that is easy to handle (not too heavy since pots need to be move in and out of garage in spring), drain well but does not need too frequent watering to accommodate my frequent travels in the summer. Mixing a general purpose premium potting soil with equal part of pine or fir barks or soil conditioners is what I settled with. Plus top dressing with mulch. I will closely monitor drainage next year and report back. The last two years all potted JMs have been doing exceedingly well and healthy. Very rewarding with not too much maintenance. I have also been using similar mix for other perennial plans (hostas, hydrangeas, heucheras) for the last 7 years with success.

Thank you all for the suggestions. I have a large detached garage that should be perfect for overwintering potted maples.

Stuart, I just ad lib :-)) I tend to add more peat and perlite (and sometimes turface or grit) than is standard to reduce such frequent watering requirements in summer. We have very dry summers here :-))

So when I make the 5 1 1 mix should I do 2 parts peat instead of 1 part? I didn't realize I might have to water every day. 80's and 90's is common in the summer here.

Stuart, 511 or 521 likely behave similarly for tree's health. You can stay with 511 and surface dressing with a layer of mulch (I use pine barks, see pictures at the top of the thread), which will help to keep water from evaporating in hot and dry summer days. Whether you need to water daily or less, will depend upon the size of the container, and location, etc. When not sure, I always use the finger trick to check (stick finger into the soil deep ~ 1 inch. if moist, no water). Most people tend to over water containers, therefore good drainage becomes even more important. My mix is probably a variation of 511: The potting soil I used contain a blend of sphagnum peat moss, aged bark fines and perlite. I add equal part of pine or fir barks (~ 1/4" size) to the above mentioned potting soil. Sometimes I use soil conditioners (composed pine barks) instead of pine or fir barks in the mix

Hope this helps

Nothing but gold! Thanks for sharing.