Last year, I watched as a beautiful Grinnell’s Penstemon withered and died over a timespan of about two weeks. It had spread to about 3 feet wide since I planted it, starting from 6 inches high and barely five inches wide. It had bloomed during Spring and looked completely healthy and happy.
Until it didn’t.
The leaves all curled and it took on a sickly purplish color. Then it shriveled and dried up. It was dead. Had I watered it too much? Not enough? Was it getting too much shade? Too much sun? Did it get a disease from the soil? I had lots of guesses but no way of knowing what killed my penstemon. So, I contacted a graduate student who was working over at the Rancho Santa Ana Botanical Garden Grow Native Nursery and asked him what happened. I sent pictures and described as much as I could. His answer? No idea. He said, “If you can figure out why any plant dies then you have answered the million dollar question.”
I guess it makes me feel a little bit better that even someone with a formal education in gardening/botany can be as mystified as I am. But, it’s also a little bit frustrating. How are we supposed to keep our plants alive if even experts aren’t sure how to do that?
I’ve lost several plants this summer. Heat? Gophers? Disease? Too much water? I just don’t know. The casualties (so far, the summer ain’t over…) as of today: two penstemons, three monkeyflowers, a desert willow, a black sage, a ceonothus (that I moved after it sprouted from a seed dropped from another plant), two other ceonothus that I bought, a Jeffery pine, a couple of dudleyas, and a manzanita.
The weather is supposed to be cooling off. Today the high temperature was supposed to be 95. It’s currently 102 degrees in my yard as I write this. That’s hardly cooling off! Then again, we live in the Inland Empire, a region of heat, wind, blue skies and sunshine. And, I just read on my favorite weather blog, Weather West, this has been the hottest summer ever on record. It shouldn’t surprise me, I guess, that the summer just refuses to go away.
The story of July so far is heat. My Acurite Pro 5-in-1 Weather Center has been recording the temperatures. Here’s a screenshot from my Wunderground weather station app.
The temperature chart shows the daily highs and lows from June 12 through July 12. A month ago, June 14, the high was 92 and the low was 49. That’s a big difference from July 9 when it hit 112 degrees and the low was 72. From what I understand, the really brutal part of summer for my plants is the night time when it really never cools off enough for them. My vegetables, especially, seem to be suffering. I’ve got a drip irrigation system on them now, so they are getting the moisture they need. But, the heat seems to be affecting their production of fruit.
My native plants are adapted to the heat. Many of them go dormant in the summer. While there is variation among the plants, the cycle seems to be that they conserve energy during the summer. Water is pretty scarce so they survive instead of thrive. But, when the temperatures cool down in the fall, they prepare to grow and by the late winter, most California native plants are blooming and growing. For example, my desert willow trees drop all of their leaves during the winter and look dead. But, if you look, there are buds on the branches. When the weather warms, the tree sprouts leaves and grows. The summer is about flowers, seeds, and survival. A few plants, however, especially the younger plants, are still growing! I’ve seen new leaves on some of my manzanita. The white sages’ flowers are all but gone, now, their “wands” browning and ready to drop seeds, but they are sprouting some new leaves, too. But, the biggest story of growth this spring/summer has been my Gambel Oak!
You may be able to tell in the picture above, the two branches that are tallest are completely new growth just this season. Both of them represent two or more feet of new growth! It’s a big jump for a plant that heretofore has only shown inches of new growth in the past couple of seasons.
I have been told that there is a saying among gardeners that “first they sleep, then they creep, then they leap.” This Gambel Oak was planted back in June of 2015, one of the first plants I actually put in the yard. So, in all, it was two years ago, but it feels longer. Patience is important, I guess, with gardening, but it’s hard to cultivate that, pun intended.
The heat has been brutal but looks to be letting up a little. Yesterday it hit 101 but today is suppposed to stay in the upper 90’s and the same is predicted for the rest of week. But, we had multiple days of scorching heat, over 15 with temperatures topping 100 degrees. The heat makes watering difficult. California natives don’t like water in the summer time, mostly. While I’m far from an expert on such things, my understanding is that the native plants have adapted to the heat and the nutrient-poor soil by working with microbial organisms in the soil. These bacteria live on the roots of the plants and they fix nitrogen, I believe, that the plants then take in. The bacteria thrive when soil is cool and moist or warm and dry. But, they don’t like warm, moist soil. Too much moisture in the warm soil kills California native plants and some are more sensitive than others.
For example, I have ceanothus plants that absolutely HATE water in the summer. They even seem to dislike it in the winter, too. The leaves turn yellow and fall off if you water them too much. But, on the other hand, some of the plants do want some summer water, particularly if they are in the first or second summer season. I have this really great book by Helen Popper titled “California Native Gardening: A Month-by-Month Guide” in which she writes:
Do not overwater. In most of the state, summer water wreaks havoc with life underground. Not only does overwatering in the warmth of the summer promote the growth of fungal pathogens that lead to root rot and crown rot, it also harms beneficial fungi that link to their roots and enable them to take in nutrients and water efficiently. These links, called mycorrhizal links, enable the plants to ward off diseases, help them recover from drought, and improve the structure of the soil. The mycorrhizae exist in mature native gardens but they take time to develop in transitional gardens. Overwatering (or overfertilizing) disrupts the establishment of these unseen important relationships.
Overwatering also causes other problems. It needlessly encourages weeds and garden pests, such as aphids and gophers. In the parts of the state where irrigation water contains salts, watering during the dry season also causes salt to build up in the soil. While it is tempting to provide extra water for faster growth, hold off for now. Instead, water the soil deeply for survival, and hose off the plants once a month for looks. Irrigate, if you like, to stretch the natural rainy season forward a bit in fall and to push it out a bit in spring, but use restraint in summer. (Popper 128)
I try to follow the advice. But, we have had multiple heat waves over the last few weeks. I started this post a week ago and the heat is still hitting 100 every couple days and when it doesn’t, it’s still in the high 90’s. And it has been very dry. It feels better to us for the humidity to be low, but plants need some water. So, even though I think I shouldn’t, I feel like I should go out there and water.
The thing is that many California native plants need a couple years of water before you can let them be during the summer. In a couple years my backyard should need little to no water at all. Only when I plant something new will I need to go out and actually water. The website for the Las Pilitas Nursery is another treasure trove of information for California native plants and the author, Bert Wilson (now deceased), recommends spraying native plants to rinse off dust, but otherwise, not to water them. That’s what I try to do. But, some of my plants are still very young while others are close to being “established” in the yard, meaning their roots are developed and extensive enough to support the plant through heat and drought with minimal assistance.
The worst part, for me, is that I lose some plants anyway. My sticky monkey flowers always seem to brown and die in the heat. I’ve lost four of them this summer and several last summer. And the sages can sometimes wilt and die back in the heat. The worst hit has been my vegetables. My pumpkin plant stopped producing fruit after one pumpkin, as did my butternut squash plant. The zucchini vines withered and the tomato plants are struggling.
And, another issue related to this is that the wet soil attracts gophers. So, I had started watering more broadly over larger areas to try and confuse the gophers as to where the roots are, since I’ve had a lot of plants killed by the awful rodents.
My least favorite weather event by far. Wind. I hate it. I’m not talking about a breeze, a gentle stirring of the leaves. Nor do I refer to wind that is good for kite-flying and refreshes the atmospheric conditions. No, I speak here of gusting, tearing wind. Wind that blows and batters and blasts the land, the trees, and all that stands in its path.
Here in the sun-kissed Inland Empire, we get a hefty helping of this wind. I know, it’s my fault for buying a house below the Cajón Pass. Said geographical feature acts as a wind tunnel, it seems providing a natural easement between the great Mojave Desert that abuts the San Bernardino and San Gabriel mountains and the Inland Region that leads to the California Coast. This easement is the path of least resistance when there is a pressure difference between those areas. If an area of low pressure sets up off the coast, and high pressure is situated in the desert, then wind will rush through the Pass and eventually over my yard on its way to freedom over the ocean.
Like a young child let out of school for the summer, the wind breaks headlong toward, with speed and heedless of anything between it and its desired destination. This rough passage has an impact of no small import on my landscape.
As I walked around my yard, I find that where I used to have 1-3 inches of mulch (red bark, mostly), there is now bare ground. The aforementioned mulch is gathered in places I wish it was not, such as the base of my young Cleveland sage, which now has 4-6 inches surrounding it. The wind breaks some of the branches of my plants. A couple were entirely snapped off of their main trunk, effectively killing the plant. I believe I lost today a penstemon, a milkweed, and a monkey flower. I saw one of my Chickering Cleveland sage lost a major branch, too.
Besides doing physical damage thusly, the wind is also dry. Very dry. The humidity today is currently 15% and dropped as low as 12% yesterday. My understanding is that this dry air has a desiccating effect on the plants, in some cases wicking moisture from the leaves and branches, not to mention from the ground. Ideally, mulch should mitigate this, but not if the wind manages to blow that mulch aside.
So, even though we just got weeks of rain and that brought 11 inches to the ground, I still had to go out and water my plants. Dry, young plants are less supple and weaker, more prone to breaking off. Their leaves shrivel as the dry air blows across them. Some of the plants, like manzanita, have leaves that don’t lose as much water. But, for the younger plants just installed this last season, I have to water them, too.
Rain, at least, will give us much needed moisture. Cold and hot temperatures give the plants a sense of season, reminding them to grow, to sleep, to flower, etc. But, wind? Wind doesn’t offer me anything. It makes a mess. It blows trash into my yard, moves furniture, knocks over containers and as I mentioned before, scatters my mulch.
And, listen, lest you, dear reader, get the misconception that I’m airing a grievience over a brief event, an occurrence that is evanescent in nature and I ought to simply hush. Well, please find it in your heart to understand that this wind has been blowing since Thursday. That’s four straight days of wind averaging 13 mph. That’s the average. And, I just checked, we’ve averaged 13 mph for the entire month! We had wind like this in the middle of the month, too. My weather station recorded a high wind speed of 20 mph January 14th. Yesterday, we had a gusting wind that hit 22 mph. Imagine getting the plants in your yard, putting them in pots, then strapping them to the roof of your car and driving around for four days around the streets of your neighborhood. You drive the whole time, too. Vary your speed if you like, but average about 15 mph and that’s what is going on with the plants in my yard.
Four days. This wind is forecasted to blow through the night and into tomorrow morning, but it is supposed to, at least, begin to subside and be a much more manageable 5-10mph. Still, I hate this wind. There’s just no good from it, to me.
My region of Southern California is often dry. Total days of rain are usually few, less than 30, I’d say. Additionally, inches of rain average between 10 and 15. But, in the last several years, California, and here specifically, has been in the grip of severe drought. I estimate that we got something like 6 inches of rain all year last year (by which, I mean, the “rainfall year” which typically is said to begin in October. This month alone we have doubled that. In January, my weather station (which is probably fairly acurate but not necessarily precise) has received nearly 12 inches, and will most likely exceed that today.
I’ve become much more aware of the weather and rainfall since starting my garden/yard. The majority of my plants are drought tolerant. They still need water and in times of drought, they need supplementary irrigation. But, I think I may not be watering much this Spring. In fact, more than half of my plants have been in the yard over a year. My understanding is that after a year, California native plants are “established” and need significantly less water. For some, that means none. There’s a great site, Las Pilitas, that is primarily a nursery but is also a treasure trove of information about California native plants. On that site, they specifically state that most truly drought tolerant California native plants hate water after the first season or two. For example, I have a few different Ceonothus species. These are also known as California Lilacs.
Ceonothus plants, as far as I can tell, hate water, especially when it’s warm. They will accept water when it’s cold, like right now, but that’s it. What I have read is that there are microorganisms in the soil that live when it is either cool and moist or warm and dry. Warm and moist soil kill these microorganisms. They are what provide nutrients to the roots of many native plants! This is why, by the way, you also should not amend California soils when planting natives, and do not add fertilizer. Apparently these mycorrhizae feed the plants are vital for their growth and survival. You might say that if you are a gardener of California natives, you aren’t growing the plants so much as these mycorrhizae!
So, I have killed at least two Ceonothus plants by watering them too much. I’m doing better with the ones I have right now. I have four that have been in my garden over a year now. Two others were growing and looking good but they were eaten by gophers. Speaking of, I just read as I was getting links for this post, that gophers tend not to eat plants that aren’t being watered!!! Oh yeah! So, maybe this year will be better if I’m not watering so much, then maybe the gophers won’t eat so many.
That doesn’t mean my hose will be idle. About once per week, I will go out and “wash” the dust off the plants by spraying the leaves. This won’t really water them but it will keep them from getting covered in dust, something else they hate. That will be nice to just go spray my plants down and not worry about watering deeply. Let’s be clear, though, this only applies to established plants. For the plants that are still young and in the first season, I will definitely be watering those plants (and keeping an eye out for gophers!).
The rain coming down right now as I write this means I will probably not water any of these established plants at all this Spring. We’re having a good year for rain, even by California’s standards. It looks like we will at least meet the “normal” averages for rain and that should make my garden very happy.
Since finishing the paver patio/pathway, I’ve been resting a bit. I get back pain due to a bad S-I joint. It’s been nice to rest and maybe just stroll around the garden a bit, but I’m also thinking about the next thing. The south side of my yard is small, gets some shade, and I’m planning to put in vegetables, fruit trees, and herbs. I have two raised garden beds ready to go and plan on maybe a third. The area needs some work, though. There’s a lot of soil that was removed from the front yard when we put in some additional concrete for parking. And, the retaining wall I installed needs another 15 feet to really be finished.
My idea is to bring the wall over and curve it a bit, similar to how I have it on the north side. That will give a slightly raised area. Then, I will try to level the rest of the area and plant lime, orange, and avocado trees, one each. I have some heirloom seeds on order for vegetables and herbs.
And, of course, I’ve never really done gardening like this before. I had a tomato plant in 2015 that never really made it through the summer. I’m guessing I didn’t give it enough nutrients in the soil. But, I plan to have the beds have much better soil and fertilizer. They have hardware cloth across the bottom so that should keep at least the gophers out.
Rain has been much better this year than last. I remember going all of December with no rain. This year we’ve had over 5 inches since October! Most of it came in the last week of December. That’s great for my garden. I’m very interested to see what happens with my California native plants. I have California Buckwheat, manzanita, and sage that have been in the yard over a year now. My understanding is that after the first full year, the plants are usually established in the garden and they require little to no water.
In November I attended a workshop at the Rancho Santa Ana Botanical Garden nursery, called Grow Native. They sell, as far as I know, only California native plants. Anyway, one of the workers, a young guy who is studying native plants in school and sounds like he has a lot of experience gardening/landscaping, gave a workshop on planting and watering. To summarize, you did a hole twice and wide and 1.5 times as deep as the pot the plant is in. Then, you fill the hole with water, let it drain, then fill it with water again, same. Then, install the plant with the base of the plant about an inch higher than the surrounding soil, then water it again.
After that, I didn’t water much. I had some bad luck though with plants I bought in the Fall Planting Festival at Grow Native. We got some really damaging winds in November. I always seem to lose a plant or two to the wind. Sticky monkey flowers do not seem to respond to the wind well, at all. Also, four penstemon (electric blue) died. They just turned black. I don’t know what happened there. It wasn’t lack of water. Maybe the heat got them. Or, a disease. But, anyway, they died. Then, many of the sages I bought got a powdery white mildew that hasn’t gone away. The black sages and the Cleveland sages all got them. I was careful not to get water on the leaves and that never happened with the plants I have now. I’m waiting it out to see how it goes. I lost two Bee’s Bliss plants to that mildew. Bummer
Most of my plants seem to be doing well at the moment. I’m seeing some new leaves growing on the manzanitas and sages.
An eclectic mind garden. Cultivate, prune, mulch, compost.