A Trip to Suncrest Nurseries

Jim Marshall, General Manager, and propagation staff

Along with my horticulture class, I recently enjoyed touring Suncrest Nurseries, in the company of Jim Marshall, general manager of the nurseries.

As it happens, I come to this nursery one Sunday morning a month to work with the CNPS propagation group. It's quiet then - now there were workers all around, doing various purposeful things, taking a break at the ring of a buzzer, and beginning work again at the next buzz.

The propagation team above was sitting at a stainless steel table, in the propagation prep area of the greenhouse. The table is sanitized daily at least with a solution of quaternary ammonium. Another way is using a half to two percent solution of bleach. In general everything in this nursery was clean and neat.

In the room next door, another team was expertly popping rooted cuttings into two and a half inch "liners"  or "rose pots," which are three and a half inches deep. Jim said they have had better success and healthier plants with the deeper liners, and in general with hand propagation rather than mechanized propagation.

Jim gave us a short history of the nurseries - which have been continuously operating since the 1880s. They were started by Leonard Coates, one of those sickly young Englishmen (born in 1855 in Saffron-Walden - lovely English country town name) who came out for the healthy life in California. He learned the horticulture trade and thrived, having most of his nurseries in Napa county. He produced 150,000 fruit trees per year for the burgeoning orchards that filled Santa Clara Valley and other fruit growing regions of California with heavenly scent every spring. He also enjoyed native plants, and propagated them too. He sold the nursery to to Ray Hartman (Heard of Ray Hartman ceanothus?), and the nurseries passed through various hands and existed in various locations before settling here near Watsonville, under the ownership of horticulturist Stan Iversen and a group of investors. Stan was named Santa Cruz County Farmer of the Year this year. I enjoy learning about the history of my adopted region, and about these horticultural pioneers.

The Watsonville area was also singled out by Luther Burbank as one of the best growing regions in California.

One of the best growing regions in California

Many nurseries are located here, seven miles inland, where the fog usually burns off by 10 am, and is held off by downdrafts from the Blue Sierra, or Sierra Azul, hills (well you can hardly call them mountains). The maritime influence keeps temperatures mild. If it gets into the high 80s in summer, “Everyone here falls over with heat prostration,” Jim said. Winters are mild too. Usually only about 10 frost days, and generally no lower than the mid 20s Fahrenheit. 

As Jim talked, I was observing with interest the professional cutting cutters' technique (see first picture). They were snipping the leaves with small clippers, not stripping them by gripping and running down the stem with their hands like I do. They were working on some kind of nepeta, I think? 

Expertly prepared. Lower leaves and apical (top) bud snipped, and larger leaves cut.

I should have asked them if they use the same approach generally or just for tender cuttings.

Not sure what all these cuttings were. Pretty though.

Our native fuchsia flowering gooseberry, Ribes speciosum 'Rana Creek' was in one of the baskets

The market for Suncrest Nurseries plants is independent nurseries, some retail and some wholesale, and landscape contractors. Eighty percent of their business comes from the surrounding 100 miles, but they sell up and down the state also, and have four or five large trucks to deliver their plants.

I enjoy unloading the Suncrest truck at our CNPS plant sales; it's like Christmas twice a year! This nursery is very kind to the native plant society indeed, with the support they provide. They care for all the plants that we work on each month. Jim said he enjoys walking through the area they have set aside for our plants, to see what we've got growing there.

Suncrest is a propagation nursery, and they sell about half their plants to other nurseries to grow out. They have about a hundred workers in the full swing of the season, and forty-five or so of them are full time workers.

Suncrest also grows an unusually wide variety of plants, about half of them California natives, and most of the rest from other Mediterranean climates - Australia and South Africa mostly. While other nurseries grow 400 to 1000 varieties, Suncrest grows about 3000, in smaller batches. This makes them more resistant to a financial crisis if a crop fails. In monoculture greenhouses, a crop failure can spell disaster.

The propagator has cut a trench for the cuttings, with a flat blade tool

I'll have to try the way of planting cuttings by making a trench with a tool like they use at Suncrest, a blade with handles - I didn't get a picture of the tool. Each cutting is also dipped in rooting hormone.

And here is where they go to grow some roots  - Wow!

During phase one of growth: the cuttings are given TLC while they grow roots, two to three months on average. The cuttings get bottom heat from tubes running along the benches, and in dry weather, mist. They are not getting mist right now, since the air is humid anyway. It's light intensity that controls the misters. At this time of year, they are being hand watered.

Mist in the propagation house was the big breakthrough that made growing by cuttings feasible in nurseries. Before World War II, propagation was done by hardwood cuttings only, which was time consuming. But with mist, nurseries could grow from softwood cuttings. Much faster and easier.

In the prop house the minimum temperature is around 65 degrees. They don't heat the air, just use bottom heat, which alone costs about $8K a year. Most of the rest of the electricity cost comes from pumping well water, which is used here. I should also mention that when the nursery was being redeveloped by the Iversen group, a lot of drainage infrastructure was installed, and all the runoff drains to a pool for reuse.  This place has been thoroughly thought through.

Tubular underbench heating.

I splurged on a small heating pad a while back but I haven't used it yet. It is only now getting cold enough, really. I should try one flat of something with heat, and one without as a control group. I also decided to try a few hardwood cuttings myself this year. A new venture - I'll let you know in a few months how it goes.

With humidity come fungi. Circulating horizontal fans are used in the prop house to eliminate grey mold, - aka refrigerator mold - which is everywhere, but is deterred by just a bit of air flow.

This is as good a point as any for some dry facts about Suncrest's potting media:

• Rooting mix: 90% perlite 10% peat moss.
• "Canning mix" - i.e., general potting mix for liners and larger pots. I think 25 percent each of peat, sand, bark, and perlite. Or anyway 25 percent perlite and the rest some combination of the other ingredients. Plus a little slow release fertilizer.

Canning is a local term. Originally, cans from the local canneries (Think "Cannery Row!") were used for potting on to one gallon and five gallon containers. Suncrest buys their soil mixes from a nearby commercial soil mixer. Soil mixer: oh, the many trades that you don't ever think of.


The greenhouse doors and main passage ways are wide enough to allow access to small vehicles. But wait, this isn't just anybody's small vehicle...

This is the small vehicle of famous horticulturalist Nevin Smith, one of the leading lights of the native plant gardening tradition, and I was very happy to be able to shake his hand.

Nevin wasn't casting a spell upon the cuttings, just talking to Jim about irrigation (as I recall).

Nevin has his professional home here at Suncrest. Suncrest also has a relationship with an Iris expert, whose name I didn’t catch, and with John Greenlee, who won the American Garden Writers award for his book The American Meadow Garden, photographs by Saxon Holt. Suncrest and John Greenlee are jointly developing a "graminetum" for grasses (like an arboretum for trees). Next year, they'll have an open house. I'm curious!

In general, Suncrest grows a lot more grasses than they used to; grasses in the landscape are definitely popular these days.

Rooted cuttings. Plants are also grown from seed 

Rooted plants are popped into liners for two to three months or more before potting on into gallon pots. 

This huge and amazing greenhouse complex was installed three years ago by a local company. In fact, the owner of that company lives on a hill overlooking Suncrest, so Jim figured he'd have to do a great job for them, since he'd have to look out on his handiwork every day! The greenhouse was built in Holland and assembled on site. It took twenty workers two weeks to assemble. Every piece had a serial number. It cost $800,000 and another $200,000 for the fittings. It is certainly a beautiful greenhouse, really a pleasure to walk through. Everywhere is impeccably clean, functional, and unfussy.

It's called a "venlo" style greenhouse. Where a traditional greenhouse might have one steep peak, a venlo style roof would have three shallower ones. This design allows for more peak vents, which improves circulation, and provides more convected cooling. (Sorry, I didn't get a photo of the outside but you can see some images of this type of greenhouse by clicking the link above.) It's made of a galvanized steel and aluminum framework, with acrylic bi-wall glazing that comes with a 50 year guarantee. Are we drooling yet?

Outside the greenhouse itself are other large protected areas for the next phase of growth, in the liners.

Liners in the shade house. Less protection begins to harden off the young plants.

Plants get pinch pruned several times in the shade house phase. That's something I really need to learn to do. And know when and how to do it to different plants. I'm so afraid of mangling their growth for ever.

They are experimenting with a topping of crushed walnut shells.

 From this shade house area, crops are staged as needed for sale, that is, they are not potted into gallons and grown to full size until it's time to put on that growth spurt, to be ready at the desired time. For example, they may have 40,000 liners of Arctostaphylos 'Emerald Carpet' that they grow on in stages to provide a steady supply of this popular ground cover manzanita to the nurseries and landscape contractors.

Major aha for me! I didn't realize that you can keep plants small for a long time in liners and they won't become stunted or root-bound. I've been doing the wrong thing, immediately potting on plants that have filled their liners in spring, when I won't be planting them till fall. Now I do recall Denise in the prop. group saying something similar. It can take a stubborn brain a while to overcome preconceived notions. Well, live and learn (eventually).

Another view of the shade house.

 And then finally, they are potted up into gallon pots.

More of the crushed walnut hulls, here topping gallon pots.

When it is time to pot them up, a machine fills the pots and drills a planting hole, but again, it's a human that does the actual planting - not like at the mass market nurseries where plants are literally never touched by human hand from start to finish. The walnut shells are a byproduct of the nearby nut industry, just north of the Bay Area, and Jim says they prevent the growth of unsightly liverwort, and other undesirable stuff like mold.

One of the few machines: it fills pots and punches a planting hole

And finally, off they go, neatly stacked.

Well as you can tell, I was totally fascinated by this trip, and I appreciated Jim's openness to talk to us students about the realities of running a medium-large nursery of this type. I'll write soon about our other stop of the day, at Sierra Azul, a smaller retail propagation nursery run by a husband-wife team, just a mile or so away from Suncrest, which was also totally fascinating, on a more individual scale.