Growing Japanese Maples in Southern California
Some plants are slow growing; some are slow to establish. Here, Japanese Maples are more slow to establish than slow to grow. Once they are accustomed to their site, and have developed the start of a good root system, growth has been reasonably fast. Note: I do not say fast, I say reasonably fast, about 18" per year, after several initial years of no growth at all. These are plants for the patient and the attentive gardener. The satisfaction comes, but it may take a decade. Yes, a decade. Are you game?
Before the satisfaction, however, the gardener must endure two or three or four or five years when nothing much seems to happen but burnt-tipped, miserable-looking foliage, dried stems and no apparent growth. Best results will be obtained, of course, in Sunset zone 24, our zone with the least amount of heat and most amount of cool ocean-delivered humidity. In 23, I've had success, but it has taken time. The greatest mistake was not buying specimen-sized plants. I took the inexpensive (small plant) road.
Now that I know they will grow in my garden, I would be reasonably confident in buying a larger specimen-sized tree, if I had the money to spend, and a perfect spot for planting (neither is available). You may still need patience to get even a large specimen to establish, just not as much patience as for a little one.
Since I was doubtful of success I bought small fairly inexpensive plants, two two-gallon sized for less than forty dollars, each just 20 or 30" tall. The third was a one gallon for $15. Contrast this with the price of an excellent specimen of 5 to 8 feet (1.5-2.5 m)--one of those may cost three to five hundred dollars. After nine years, our 30" 'Oshio Bene' is now a little over 11 feet (3.5 m)--is it worth three to five hundred dollars now? Hmmm, probably not. It might cost that much to wrangle it into a 36" box, and there goes that. But to me it is priceless, since I got to watch it struggle, then grow and prosper.
'Oshio Bene' only starting to leaf out, so it looks funky. Wait two weeks!
Our 20" 'Ever Red' is only 36", but it is a cascading shape wider than tall. It's currently swallowed up by a blooming Geranium madeirense, which will be dead in about a month and a half (normal behavior: Geranium madeirense die right after blooming). 'Ever Red' will be fine covered up for another few weeks.
'Oshio Bene' three or four springs ago, when it was 7 or 8 feet:
'Emperor I' was in poor shape when we bought it as a 50% off 1 gallon in the heat of summer a couple of years ago. Planted in a decent spot on the north side of the house, it has grown perhaps six inches. The first year a rabbit ate every bit of foliage, leaving the stems for a future meal; before that I corralled the little tree with protective wire fencing. It grew no new foliage and sat leafless for the rest of the season, but it had healthy foliage in year two. It looks well this spring; I hope for growth. This cultivar can get 15' (5 M) or more.
'Emperor I' leafing out inside its rabbit guard:
Because they like acid conditions, being understory trees (trees that grow under the canopies of larger trees), camellia/azalea mix and a bit of soil sulphur every spring to reduce pH in high pH Southern California is a fair idea. Many named varieties are grafted plants, so mind the bud union, which is usually up several inches from ground level. Planting them under a large tree with a well-behaved deep root system is ideal. Many people in Southern California keep them in large pots on a shaded patio.
I tried that first. Our brutal, dessicating Santa Ana winds did the little trees no good, so I put them in the ground on the north and east side of the house. 'Oshio Bene' actually gets about eight hours of sun. It struggled the first couple of years in the spot, but having grown to eleven feet, it seems to have adjusted. I make sure the root system is always well-mulched with good compost to help keep the roots from drying out. They like steady moisture but never soggy soil.
Dead twiggy tips: not to worry!
At first I worried about the occasional dead twigs at the branch tips. Then I saw an old "Gardeners Diary" TV episode about a visit to a Japanese Maple grower in the Southeast, the grower casually picking off many dead twig tips as she discussed each plant. If it happened in the humid moist Southeast, it wasn't my fault in dry low humidity California. Stopped worrying about that, and now I nip the dead twigs off with a bonsai scissors. Remember "Gardeners Diary"? I liked that show.
Here with our lack of fall frost there has never been spectacular fall foliage color, as there is in colder climates--the leaves simply turn brown and drop. Yet we grow Japanese Maples anyway--their beauty in spring is enough--more might be unbearable. Okay, okay, I exaggerate--of course I could find it in my heart to bear blazing fall foliage color. Just not the frosts required.