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Category Archives: Plants
Alcatraz these days is a bustling place of projects. The big project of repairing the west side wall of the cellblock is very apparent but visitors can’t see the work being done as the scaffolding is wrapped in white plastic.
The other significant project that was just completed at the end of December was in full sight of visitors and left a dramatic difference to the island. The Eucalyptus grove at the south end of the island (just off the dock), was removed. The project had been two years in the planning and finally had enough urgency and funding to make it possible. The trees, originally planted by the military in the early 1920s, had reached maturity and were a safety risk of falling.
Marin County Arborists were trusted with the tree removal. The company had previously worked on tree removals on the island and was familiar with barging equipment over and working around visitors.
Sixteen blue gum eucalyptus trees and two non-historic Monterey cypress trees were removed and chipped over three weeks.
The chips were hauled to the Parade Ground to be stored until the National Park Service’s archeologist had a chance to examine the bare slope for evidence of military construction. We received the ‘all clear’ within a day of the trees being removed and we set to work!
First, chips from 18 trees is a heck of a lot more than I could envision! The recommendation from consulting arborist was to put the chips back on the slope to a depth of 4”, place jute netting over top and anchor wattles horizontally across the slope to stabilize the slope. The slope had been eroding badly for years, so this would be the perfect opportunity to stop the erosion.
Volunteer groups were enlisted to manually place the chips on the slope. With bucket brigades and teamwork, the slope was covered over a month. The Golden Gate National Parks Conservancy’s Stewardship Team (of which the Alcatraz Gardens is a division within the company’s organization) were set to take a day off from their normal sites and lend a hand. To sweeten the deal, an overnight was planned (and what better way to say thank you than a night in solitary?).
The effort was a huge success with people filling
buckets, people carrying the full buckets to the bottom of the slope, to the chain of people to send the full buckets up the slope, and empty bucket retrievers! Maria Durana captured the well-oiled machine of the bucket brigade:
Once the chips were in place, the jute netting could be placed on top. The rolls were heavy and we soon figured that cutting them first was best.
Aside from the Stewardship Team, four corporate groups and the regular drop-in garden volunteers pitched in to help spread the mulch. In total 900 yards of jute netting was placed and 750′ of wattles were installed.
The slope will be replanted with Eucalyptus cinerea ‘Pendula’ in September 2017 in keeping with the historic look of the island.
On another note of discovery, the perimeter wall of the Parade ground was further revealed along with the basement of one of the former cottages. And a new fern was found growing! With more years of planning to come, hopefully this neglected garden are will be the next focus of garden preservation.
The island’s first purpose as a military prison introduced the construction of the Sally port and this is where all visitors first walk by today on their way up to the cell house. Before entering the Sally port, they are greeted with the island’s first garden and home to some survivor plants thought to be planted in the 1920s. Among this bed are two historic Cordyline that are very old and are showing signs of decline. The Cordyline australis planted in the Sally port gardens is an old variety and have been very hard to find in the nursery trade. The Cultural Landscape report suggests that these be replaced, but not until we have the same plant with the same genetic makeup of the replacements.
In efforts to replace these declining historic Cordyline, we have tried several propagation methods to ensure they remain as part of the gardens for years to come. All of the methods were done in mid-March and we recently have had some promising results. Below are detailed descriptions of the propagation techniques trialed.
Methods of Propagation
We first tried just a cutting of one of the canes and potted it up in a pot of our compost. We removed some of the foliage and trimmed some of the fronds back to reduce that amount of energy going into the foliage and instead put it into the formation of roots. At first, it seemed as though this method might work, but after about a month, the fronds were almost all dead. The cane itself had become soft and the inside had become rotten. I think this method would work using a thinner cane or a smaller one with less foliage.
For this method, we took three pieces of cane, about 6 inches long each and laid them horizontally, half way deep, in a tray of sphagnum peat moss mixed with our compost. I had thought this method would work best, and we actually did have roots start to form alongside the canes, but I think they ended up getting over watered and the canes started to rot. Unfortunately, all three were unsuccessful. I think if we were to try this method again, we would use a different media composition and not allow the soil to get too wet.
The air layering method turned out to be the most successful of the three that we tried. This method is actually done on the mother plant itself. We started by soaking sphagnum peat moss for a few hours. This is crucial to keep the stem moisturized to allow roots to form. On one of the canes, we cut an inch wide ring through the cambium layer and removed the bark around the cane. Next, we took the soaked peat moss and wrapped it around the cut tightly and then wrapped it with plastic wrap and tied string around it to hold it in place. We did this twice more on separate canes. We recently cut the three successful air layered canes from the mother plant because roots had formed and they were ready to be potted up. We first soaked them before potting them to allow the peat moss to rehydrate. We put the new plants in five gallon containers and they are happily living in our greenhouse until they reach a more mature state with more developed roots to replace the ones at the Sally port.
The air layering method can be used for other woody shrubs and works well for some trees. This method does take a while to see some roots form, but once they do and it is cut from the mother plant, you already have a bigger plant than you would if you propagated it by seed or a cutting.
To replace the survivors, it is important that they are replanted with the same species of the current Cordyline. By propagating them by the methods we tried, it ensures that the replacements have the same genetic makeup of the current plants. We are very excited to have successful clones to replace the current failing Cordyline.
The gardens were fortunate this summer to have two youth interns through the Parks Conservancy youth program. As they wrap up their 140 hours working in the gardens, there was still another skill they needed to know – how to select plants from a nursery.
We headed down to Pacific Nurseries, a wholesale nursery in Colma to do our shopping. Our mission was to find plants that would fill in areas on the windy west side of the island in the Prisoner Gardens. Sections of this garden are always struggling to cope with the extremes of heat and fog, wind and the curiosity of gulls, even after the gardens were restored in 2009, they still aren’t quite right.
Upon pulling into the parking area, my eyes always light up with seeing the plants laid out in groupings of perennials, shrubs, roses, succulents, annuals and shade lovers. Sometimes, I place an order and can go and have everything ready, but often, I just see what is available and chose from the vast selection.
For the Prisoner gardens we were on the hunt for perennials, mostly Salvias as the ones we already have are thriving.
We started with 1 gallon pots of Salvia clevelandii. The first thing to notice was the health of the leaves and checking that the stems are not broken. Salvia clevelandii tends to be brittle anyway so extra care needs to be taken while handling them.
Turning the pots around, it’s is essential that we are not taking any hitchhikers to Alcatraz – namely snails and slugs and weeds.
Explaining what a ‘root bound’ plant
looks like is a lot easier when standing in a nursery. While Pacific Nurseries have excellent plants to choose from, sometimes roots get circling the inside of their container and can even root into the ground through the drainage holes. Plants like this tend not to adapt well once wrestled out of their stricken home and in bad cases, there may be hardly any soil left in the pot, leaving the plant suffering from drought as well.
With plants we choose, we have to go through quite an effort to haul them to the boat to get them to the island. Checking that the plants are well watered helps the plants with the trip. The interns could feel the weight difference in pots that were dry versus heavier pots that were well watered. Of course, the growing median makes a difference too (but we’ll save this lesson for another day).
We soon had our carts full and packed the van!
While we checked out with our purchases, the interns had 15 minutes to run around and look at all the types of plants. I’m sure their Instagram accounts are full of selfies with the plants. Pulling off the freeway to come back along the Embarcadero, the van was noticeably quieter – a look into the back showed both interns had fallen asleep. Definitely a sign of a great shopping day!
The term ‘invasive’ is often misused to label plants or anything that is intrusive in the natural environment. It is something I have only recently began to question. What actually validates a plant being invasive? (I’m going to stick to just talking about plants… I am a gardener after all!) My experience with talking to the public when removing invasive or unwanted plants has been pretty limited, but this past week as I was weeding the lawn, a guest on the island asked me, “Are you weeding invasive grasses?” Without really thinking about the question, I said, “Yeah.” The grasses we were removing from the lawn were crabgrass, annual bluegrass, and rattail six weeks grass. After he walked away I was left thinking, “Are those really considered ‘invasive’?” This led me to a bit of research in pursuit of an answer…
Plants that are invasive are actually scientifically categorized as so. It seems like scientists also have trouble labeling whether or not a plant is invasive or how plants can eventually become invasive over a long period of time. Plants that aren’t native to an area aren’t considered to be an invasive species until they have a negative impact in disrupting a native area. The displacement of native species and the ability for a non-native to cause economic and human harm are the two attributes for a plant becoming an invasive species. The Environmental Detection Distribution and Mapping System (EDDMS) have a simple list of characteristics showing the differences between an invasive and an ornamental plant:
The three grasses we were removing from the lawn are actually not on the invasive list for California. They are weeds, unwanted in our native sedge lawn, but aren’t labeled as invasive. Plants can however become invasive over a period of time. Because of this, it’s important to monitor non-natives and their growth in native areas.
This graph is a good representation of how plants begin to become a threat to natives and the actions that should take place to keep it under control.
During the lag phase and early recognition is when it is less costly and easier to eradicate. To prevent plants from reaching levels of higher efforts to control, it is crucial to catch them and be aware of the plant’s potential threat to a native area.
So, with all that being said, let’s see if we can clear up some misunderstanding on a few plants that call Alcatraz home. I think my favorite example, is the Echium candicans or commonly known as Pride of Madeira. It is a plant native to the island of Madeira, but has been introduced to the coast of California and thrives very well here. Many think that this plant is invasive because it is found among the hillsides and coastal bluffs mixed with native plants. Although it does spread fairly easily, it has shown no threat to native plants and is listed on the California Invasive Plant Council, (Cal-IPC), as a limited threat. It is a well admired plant on the island and copes well with the high winds and little rainfall. It is an island survivor plant that has naturalized itself and is a great pollinator for bees.
On the other hand, English ivy, (Hedera canariensis), is a plant that is considered to be a high threat on the Cal- IPC list. It is found all over the island and was one of the more prevalent plants contributing to the overgrowth in the gardens and is still a plant that we are consistently working on cutting back to keep it at bay from the garden beds. In other overgrown areas though, the ivy plays a vital role during water bird nesting season. They use the ivy overgrowth as a nesting site to lay their eggs and raise their young. Himalayan blackberry (Rubus armeniacus), is another plant found on the island that is listed as a high threat and we eradicate it from the garden beds, but leave it be in overgrowth areas because the birds also use it for nesting.
Jupiter’s beard (Centranthus ruber), and Mimosa tree (Albizia distachya), are examples of plants on the island that are commonly mistaken as invasive. They both are island survivors and spread fairly easily, but neither is listed on Cal-IPC as invasive. We like to use the term ‘aggressive’ and we monitor them and remove any unwanted seedlings. The mimosa tree is a nesting site for Anna’s hummingbirds and Jupiter’s beard adds a seasonal burst of color throughout the gardens.
I hope this clears up some confusion about what invasive actually signifies. Just because a plant isn’t native doesn’t make it invasive. The invasive plants on the island are kept in check and tell the story of the islands past gardeners. For today’s gardeners, you should check local plant lists for invasive species before purchasing.
Most people are familiar with the idea of a portrait – usually it brings to mind a picture of a person that captures a close up of their face and maybe tells something about the person’s personality or life. It turns out you can also do portraits for plants! Last week, I had the opportunity to go to a talk at the Marin Art and Garden Center in Ross to learn how to build a Photo Florilegium from Saxon Holt and David Perry.
Florilegia (plural of florilegium) were started by Victorians to document a specific collection of plants, usually painted with watercolors. The illustrations would be bound in a book and later became popular as framed prints. With the Alcatraz Florilegium in its final year, I was curious to see what a photo Florilegium is and hopefully pick up some tips for taking better photos of the gardens and plants.
First to speak was Saxon Holt, a renowned plant photographer who has several e-books and bestsellers. A successful garden photographer for over 40 years, Saxon had plenty to share with us.
Saxon is perfecting a technique called ‘extraction’. Done in Photoshop, close-up shots of a plant are taken. Usually a number of exposures are taken to get a portion of the plant entirely in focus with sharp edges. The plant is brought forward out of the background. This technique has many cool details that are missing in a typical hand painted illustration.
First, a photograph captures the plant where the gardener chose to put it, with the colors in the background and showing the plant in context with its surroundings. Second, a photograph only records a moment in time. The portrait captured is never going to look exactly like that again. With the ease of recording GPS coordinates, it is relatively simple for anyone to return again and again to the same plant to capture stages of the plant’s life – creating a true portrait of the plant.
One feature of the Alcatraz Florilegium
illustrations that I’m drawn to is when artists paint the brown tips on leaves, rust and when the plants are setting seed and going dormant. This is truly how the plants are.
David Perry next spoke on tips for taking plant portraits. One point David was quick to say was that you do not need an expensive camera to take great photos. The main thing is to have the eye to know a good shot.
Think of photographing plants as you would people, keep in mind that you want to tell a story. David explained that a common problem when taking photos is that most people take pictures of nouns (snapping pictures of a tree, flower or a landscape). What are lacking are verbs, adjectives and prepositions. Brushing up on grammar school, this simply means don’t take mug shots of plants. Take photos that say something.
Tips from David made perfect sense:
-Look up / Look Down – people tend to take photos of what’s in their view. With the average height of people being between 5’3” and 6’3”, most photos are from this perspective.
-First / Last light of the day is best – the best light is already gone by the time people are putting the second cream in your coffee. Stick around after sunset for the best light. White flowers almost will glow in this fading light.
-Keep going back – show different moods of the same plant in different light, seasons, capture the telling detail of the plant.
-Be mindful of what’s in the background – avoid getting houses, and you can also create your own background with sheets of patterned paper for close-ups.
-Photo apps that David likes – camera+, handyphoto, overphoto, and mextures. All of these are a few dollars each and are fun to play with.
David also said ‘it’s not fair to let the plant do all the work’. He recalls being intimidated by ‘how pretty she was’ when referring to Rose ‘Felicite Hardy’.
Listening to these energized photographers, it was easy to see why they are so passionate about plants and photography. Gardeners are passionate to plant and to care for a garden, and now another step is to take photos of the plants you have chosen to be a part of your garden – creating a Photo Florilegium of a garden that is unique from any other garden.
Alcatraz, as a Historic National Landmark, has a pretty constant look, even the silhouette view of the island from the city is considered historical. However, over the past two weeks, the look of the island has changed dramatically. Unlike earthquakes that suddenly jolt the landscape into a different look, tree maintenance can (and should be) planned for.
Like all changes to the landscape, approval from the National Park Service was essential, especially when two one-hundred year old trees are being questioned. As a starting point, the Cultural Landscape Report that was adopted in 2010, had made the recommendation for tree work on the island’s historic and non-historic tree. The difference between historic and non-historic is any tree growing on the island between 1854 and 1963 is considered historic – any tree outside of that time frame is non-historic.
Tree maintenance, and especially tree removals, are quite expensive. With limited funds, we realized we could not do all of the recommended work at once, but would need to spread it over a few years. To help us decide what work should be done right away, tree consultants were brought in. The consultants evaluated each of the historic trees on health and safety. Non-historic trees were not examined as they will be removed anyway and were not posing any safety hazards.
The consultant’s report made a few recommendations that went against the recommendations in the Cultural Landscape Report. With experts advising us, we decided to go with the consultant’s report.
To obtain the National Park Service’s final permission, a detailed description of all the work to be performed needed to be entered into the Planning, Environment and Public Comment (PEPC). A well written summary answers the 5 W’s (who, what, where, when, why) and the 1 H (how). Maps and diagrams may be attached and often help to explain to the people who review the projects who are not familiar with project sites. For the tree work, an administration approval was granted, however, sometimes a presentation must be made to a committee.
The consultant’s gave safety priority ranking and trees along the main roadway that leads to the cell house were ranked highest. The consequences of a tree falling along the main roadway would have frightening implications for visitors and staff, not to mention close down the only road that leads to the cell house.
Loud disruptive work must be completed before the annual bird nesting season begins on February 1, so a push was on to get the work done.
Sounding like an opening scene for a scary novel, the arborists boarded a ferry on a dark and stormy morning out of San Francisco with their chainsaws in hand.
Starting work on probably the rainiest day was just bad luck. Nevertheless, lines got strung up in the trees, equipment moved to where it needed to be and the next morning work started promptly at 6am with the ferry ride.
The arborists made steady work pruning the large Eucalyptus and moved onto various cypress along the roadway. The arborists were more like trapeze artists up in the trees. The crews skillfully tying limbs to be lowered to the ground instead of just letting them drop. Visitors actually cheered them on when large limbs were cut.
The amount of light and the feeling of airiness was apparent to us immediately. Often you don’t notice how overgrown a plant has become.
While it is sad that trees were cut down, it is important to remember that trees have lifespans as well. One of the trees will be replanted with another cypress and in another 100 years, we will likely cut it down again and replant. Even looking at historic photos from the military, there are many trees in the photos that are no longer there. Plus, for an island that originally had no trees, we should keep Antoine De Saint-Exupery quote from The Little Prince in mind ‘You become responsible, forever, for what you have tamed.
Not only do the kids go back to school, it’s the perfect time of year to propagate your favorite roses from cuttings!
Tapping into the wealth of knowledge from other volunteers on Alcatraz, we found out that a bird docent has a skilled hand at propagating heirloom roses by cuttings. Karen Vandergrift willingly offered to demonstrate her knack.
To start, after the rose has bloomed and before the rose hip has started to form, a cutting should be taken down to the fourth leaflet, and cut the stem ½” above the bud.
Next, pull off the leaves from the lower two buds and trim off any buds or blooms still remaining on the cutting.
Then, with sharp pruners, cut the top half of the leaves off. This will reduce the surface area that will draw moisture out of the plant.
After that is done, lightly scrape off the layer of stem down to expose the cambium that is on bottom 2” of the stem. Dip the cutting in root hormone.
Using a clean one-gallon pot, stick the cuttings in moist soil, we used our Alcatraz compost, but a potting soil mix would be fine. We put three cuttings in one pot, so hopefully one of them would take. Karen explained that she likes using a 1-gallon pot so the cutting has ample room to grow and does not need to be disturbed by repotting if it were to be started in a sleeve. She also explained that the 1-gallon pot will not dry out as fast as smaller pots.
Create a mini-greenhouse by placing skewers in the 1-gallon pot and putting a plastic bag over the skewers. The plastic bag and cutting the leaves stops evapo-transpiration that dries out the soil and the tissue of the cutting. Be sure that the leaves of the cuttings are not touching the sides of the bag as this would cause the leaves to rot. The pots are in our greenhouse, out of direct light.
We should have rooted cuttings in 6 weeks. We were instructed to water a little bit in one week – and mostly lift up the pots to see if they are light, then they need water.
If no growth is obvious in 3 months, then we’ll try again!
Help save the soil you wonder? Are we not in drought? Should we not be saving water instead?
I wondered these same questions until I listened to Dr. Stephen Andrews, a soil scientist and professor at U.C. Berkeley. Stating the fact that California is now the driest since 1580 was enough to scare everyone in the room. California depends on water from snowmelt in the Sierra Nevada that slowly melts over the summer months. The snowpack gets replenished during the winter. Without a reliable winter to bring moisture, there is more at stake than just a lack of water.
Another fact – Just 1 teaspoon of forest soil can contain 10 billion bacteria! Wow! And of the 10 billion, we hardly know anything about them.
Another fact – California has 15.5% of rare soil types and 104 of endangered soils in the USA.
The loss of a soil series is a bigger problem than losing an endangered animal. As Dr. Andrews explained – when you lose a soil, you lose the entire community of organisms supported by it. There is so much we do not know about the ground beneath our feet, that we are not even aware of what we are losing. To further open our minds, Dr. Andrews pointed out the Clean Air Act protects the air, the Clean Water Act protects the water, but there is no Clean Soil Act – very astonishing considering the soil is what we depend on for our food.
So what can the average person do?
1. Lose the Lawn
Ask yourself ‘What is your lawn doing for you?’ There are plenty of low-water lawns to choose from now, check out ‘No Mow Fescue’ or a Delta bluegrass blend.
2. Water Deeply
Two-thirds of a plant’s biomass is underground so getting water to the roots is vital. A deep watering accommodates plants as they grow over time. Water emitters need to be moved as the plant grows to encourage proper root development. If you have a tiny emitter right at the base of tree and never move it, the roots will have no reason to grow further and anchor the tree.
3. Upgrade your Irrigation System
New systems have many programs that you can set, including ‘wet weather sensors’. Be sure to group plants with similar water needs.
4. Capture Every Drop
Keep every drop in your yard, make it your goal to not send any runoff to the street. Capture, re-use and filter your water. Create a water garden, install a water catchment or consider using your grey water to water landscape plants. Be sure to use bio-degradable soap and alternate the landscape plants you are watering. On average 14 000 gallons of water falls onto a rooftop during the rainy season – this stored water could be a source of water during a fire or for an earthquake. The water tanks alongside a house can help moderate the temperature of the home as well – keeping it cooler in the summer and warmer during the winter.
5. Plant Water Wise Plants
The Bay Friendly Coalition provides a list of recommended plants for the Bay Area. Most nurseries will be able to help you choose wisely. Another tip – purchase smaller sized container plants – 1 gallon instead of 5 gallons, 4″ pot instead of 1 gallon. The smaller sized plants will require less water to get established and be under less stress.
6. Skip the Fertilizing
Fertilizing encourages plants to grow – but this new growth needs water. Feed your plants with compost. The nutrients will become available as the compost breaks down naturally.
7. Compost, compost, compost!
Use compost instead of fertilizer. Fertilizer contains salt, which is harmful to soil bacteria and burns plant’s roots. When the soil bacteria is stressed, disease has a chance to settle in. Compost is natural and will decompose over time.
Mulch is a permanent cover over the soil and can be done in layers to conserve moisture in the soil. The mulch controls weeds and moderates the soil temperatures so the plants’ roots and the soil bacteria have a happier home.
Below is a diagram of what a mulch layer looks like. The larger particles in the top layers will decompose as a new layer is added each year, thereby becoming the layering underneath.
Did you know the Dahlia is the official flower of San Francisco?
On October 4, 1926, the San Francisco Board of Supervisors took a vote and animously decided that the Dahlia best represented their city.
From the San Francisco Dahlia Society website, the proclamation reads:
“WHEREAS, the Dahlia has reached its highest perfection in and about San Francisco, and because Dahlias originated in San Francisco are grown in gardens all over the world; and
WHEREAS, the Dahlia partakes essentially of the character of our beloved city, in birth, breeding and habit, for it was originally Mexican, carried thence to Spain, to France and England in turn, being changed in the process from a simple daisy-like wild flower to a cosmopolitan beauty. It has come back to San Francisco like the sophisticated world traveler it is, to find its favorite home here, where it thrives in the cool summers and the moist air of our fog-swept, sandy gardens by the sea;
WHEREAS, it is a robust flower, generous and able to thrive in any reasonable soil, so long as it is not too dry, and has the primitive strength of our pioneer ancestors, together with the gayety and color that no other city nor flower can hope to equal, going, like our artists and poets, to carry color and beauty into far climes, but blooming best in our own gardens out of doors in our cool even climates;
WHEREAS, in its versatility, its beauty, its infinite variety of color and form, it is the very symbol of San Francisco life and of the spirit of her people; therefore, be it
RESOLVED, That the Dahlia be and it is here designated the official flower of San Francisco.”
The reasons the Dahlia was chosen in 1926 still hold true today – San Francisco is still a world-class city – still innovating, has spirit and still has foggy, cool summers.
Since the 1920’s, dahlias have had a dedicated plot near the Conservatory of Flowers and are an attraction for locals and visitors throughout the summer. With dahlias being so popular, perhaps this is why the residents of Alcatraz began to grow them. Our small collection consists of heirlooms from the 1880’s through the 1940s. The flowers are just beginning to bloom – time to take in this history within history on a tiny island.
California has traditionally gone through cycles of drought and it was an important factor when the Alcatraz Historic Gardens project began in 2003. Restoring an island full of plants did not make much sense if there was no fresh water to care for the rehabilitated gardens.
From the early days of the preservation, there were many common sense things that were done. The simple actions of designing drought tolerant gardens and timing the planting for the winter rains were easy enough to work with. There is such a wide variety of plants that can tolerate and even thrive with little water, that this was never a hindrance to the revival of the gardens. In fact, with now over ten years of first-hand experience on the island, we have built up a list of ‘Alcatraz tested’ plants that we provide on our website.
With rain collection being a known historic occurrence on the island, obtaining approval to once again collect rain water was straightforward enough – again, this had been always been in the garden work plan. However, despite filling the 12 000 gallon catchment to capacity each year, the shortage of rainfall is not saturating the soil. This means that the gardens begin the dry season already thirsty. For the past three years, we have begun to use our stored water in the early spring, instead of months later in the summer.
We have officially entered our fourth year of drought and we wanted to be pro-active and conserve where we can. This year we installed drip irrigation to save water by watering directly to the plants, avoiding overhead hand watering. So far, the rose terrace, Officers’ Row, and two sections of the Prisoner Gardens are on a drip line. We also installed a drip line to establish the native sedge lawn in front of the cellhouse. Once the historic lawn is established, two inches of water are required each summer month – a huge saving from the needed one inch per week for the typical turf grass. The irrigation in each garden area is divided into zones, so we can water sunny areas more, and the shaded corners less often. We have also attached inexpensive water meters to each of the hose pipes to keep track of how many gallons are being used on each garden area.
This year we also are using fine wood mulch to conserve soil moisture. Mulch was not used historically, but cultivated soil was the historic look. Now, we opt for a more permaculture ‘no-till’ approach with fine ¼” mulch on top. The no-till improves the health of the soil, and the mulch will conserve moisture in the soil. The wood chips will eventually decompose, adding to the organic matter in the soil.
Another water saving tip is to use perennials and not annuals. The majority of the garden plants are perennials. Perennials are better suited with typically deeper roots that can withstand dry conditions. Aside from the recent lawn planting, our last major planting was back in 2010. The perennials are now established and can tolerate drier soil. If you ever try to pull out a native California plant versus a non-native weed, the native will put up a fight while the non-native will easily pull right out.
As the summer continues, we may opt to not plant some of the beds which typically would be planted with annuals. For example, the raised beds in front of the greenhouse have been planted with spring and summer bulbs like cape tulip, Dutch iris and gladiolus followed by summer annuals. This year, we will likely omit planting the annuals and leave the raised beds fallow instead.
As our drought continues, I am seeing more lawns being ripped out and replaced with drought tolerant options, even artificial turf. A trip to see our gardens is well worth it to get ideas for your own backyard.