Sunday, June 14, 2009


They say that you can't grow Raspberries in Davis for reasons of heat stress, hard water etc. I however, beg to differ. I have been harvesting a about a pint a week of golden raspberries out of my EC garden plot for the last month. The pint number is really a guesstimation because the raspberries never leave the garden; they seem to disappear straight into my mouth despite my best efforts to bag them to take home. A few did make it into a raspberry ruhbarb custard pie (my favorite!) But that's all that managed to make it home.

I planted the berries a couple of years ago along the north side of my perennial plot because I thought they would be a clever way of detering people from stealing my produce. The raspberries hanging over the fence would be a great foreground distraction for people, and the thorns would be a deterrent for people who did happen to notice the rhubarb and asparagus ready for harvest deep inside the plot.

I planted a couple of cultivars, Heritige, the red raspberry cultivar that is available bare root at just about every nursery in January, and Fall Gold, a golden raspberry, actually they're kind of peach colored when they're nice and ripe. The Fall Golds have far out performed the Heritiges , with two abundant crops of berries each year, one in late May and one in September. The plants are very happy and doing what happy raspberries do, spreading by rhizomes and sending up fat healthy canes everywhere, including in the paths and other beds. I plan to dig these up when they're dormant this winter. I'll give some of them away and use the rest to replace the Heritige plants that only bear a couple of puny berries each week.

I bought my raspberry canes in Mendocino County, fabulous raspberry growing country, knowing full well that none of the nurseries in Davis even sell them becuse they're not supposed to grow here (telling me I can't grow something only encourages me to plant it). My thought was that if I could mimic the conditions that wild raspberries growing in(cool, moist, dappled sunlight, acidic forest soils with a leaf litter layer on top) then they might just grow for me.

The bed I planted the raspberries in is shaded by a hop trellis on the west side and a few elm branches over the top, so check on dappled shade. Before I planted I worked lots of compost into the soil, and some bone meal too, which acidifies the soil and adds fertility, I also put down a double length of soaker hose which I use to give deep infrequent waterings (4 hours 3 times a week durning the hot part of the year) and mulched over the top of it with rice hulls, so check moist and litter layer. It's pretty sketchy to say that I've actually mimiced the conditions in the raspberry country of the Pacific Northwest, but obviously It worked for at least one cultivar, and hopefully it will work for more than that.

Since there's nothing I can do about the Davis heat I'm interested in trying some other cultivars that are supposedly heat tollerent. Last winter I planted a Tayberry, a hybrid between a black raspberry and a blackberry that is supposed to have very tasty black fruit. I'm also interested in trying other black rasbberry cultivars because black raspberries are native to hotter areas than the wild red ones. And then there's Baba Berries, no longer commercially available in California, these are the holy grail of raspberries to me right now. They're another blackberry raspberry cross, apparently they bear tons of very raspberry like fruit. Alas, I can't find plants! If anyone has some of these I would be happy to trade some Fall Gold canes for some starts.

Saturday, May 2, 2009

Spring Crazyness: Warning: long and rambling

I've been neglecting my blog- and really I've been neglecting my garden too. I've had a lot going on this month and it's not likely to slow down, so I'm working on my projects and adventures bit by bit rather than in the all day fully documented sessions that I'd ideally be blogging about. So I guess today's post is going to be a long list of scenes from my life, some of them no more than excuses, that show what I've been up to, and why my garden isn't in great shape yet.

Ok, so my last post was on April 7th. My excuse for not posting the week after that is that I was busy at work. I work on an educational farm: Center for Land-Based Learning's Farm on Putah Creek. I planned and led 4 field days that week. I really worked hard on the curriculum for these particular days and they went great! The students did a self guided rotation through stations where they learned about walnut trees, chickens and eggs, compost, soil formation and geomorphology, pond macroinvertibrates, vegetable gardening and irrigation, birds and owl pellets, flowering plants and pollinators. The cool thing is now that I have these stations put together, I can just roll them out whenever a group of kids comes to visit. We wrap up the day with a hay ride to the creek and a silent walk along the water. On the last day we saw 3 great horned owls and an otter! Sweet eh?

So the field days were fun but going to North Carolina was even more fun! After the last students left on Friday, I had to clean up the farm and pack as quickly as possible because I had a 10:30 pm red eye flight to Charlotte NC that night. I barely made it to the airport in San Francisco in time, but I made my flight and slept, albeit poorly for the next five hours while flying across the country (belive me I needed the sleep, those field days involved long late hours of prep, early mornings setting up, and lots of sprinting and yelling while the kids were around). Anyhoo I got to Charlotte at 6:30 am their time picked up a rental PT Cruiser, fired up my gps and embarked upon the two hour drive to Asheville by myself. I didn't last long though, about 45 minutes into the drive I was falling asleep at the wheel, so I pulled into a McDonalds parking lot and fell asleep.

When I woke up after half an hour I was alert enough for the scenery to make an impression on me. North Carolina is beautiful in the second week in April. The landscape is rolling hills covered in deciduous trees which were not leafed out yet when I arrived. In the understory there are dogwoods- lots of dogwoods, and they were all in bloom. It was amazing. The second hour of the drive took me along the broad river where Last of the Mohicans was filmed. This is breathtaking country folks!

I finally arrived at 'The Big House' Where Brian was waiting for me at 10 am. Brian had headed out to NC a week ahead of me because he was the best man in Sarah and Malanyon's wedding at the big house that we were there to attend. So the Big House - Also known as Sherrill's inn is a pretty amazing place. The earliest building on the property dates from 1800 and the place looks like it grew exponentially after that until about 192o when improvements on the house seem to have stopped.

The place is a huge beautiful old house that has that good old unplanned feel, the floors and walls aren't square anymore if they ever were, and there are staircases in places that don't quite make sense. There is electricity and indoor plumbing in some parts of the house- not so much in others.What's more interesting about the place though is what is inside. The contents of the house don't seem to have changed much since at least the late 1800s. The china cabinets are loaded with generations of brides' wedding china, beautiful, yet chipped and cracked from being used at celebration after celebration. All of the furniture is stuff that you've only seen on antiques road show and all of it gets used day after day by the Clarkes, the family that owns the place.

The place sees hard use too. The farm that the big house sits on produces grass fed beef, pastured hogs and broilers, eggs, and has a beautiful market garden. Annie Clark and her sister run a summercamp on the place where kids get to ride horses, work on the farm and swim in the hot afternoons. There are kids and dogs and dirt everywhere all the time. There's always a pot of coffee on for visitors... Need I say more. I loved the place; I wanted to move in, and I'm sure that they would have taken me in. But after the lovely wedding in the blossoming apple orchard, a tour of the farm, and a fabulous day of horseback riding I left totally inspired.

We checked out some other farms in the area while we were there. Asheville, it turns out is a very cool place, and I could see myself living there for a while, but I think that in the end I'm a California girl. I have to admit that I spent a lot of time on the tours of various farms remarking on how far behind us their spring seemed. In California the third week in April is time to plant tomatoes; in Asheville they are barely getting lettuce in the ground.

Ok so we had a great five days in Asheville checking out farms and hanging out with Malanyon and Sarah. We flew home on Thursday the 23rd, that afternoon I got back to work. On friday I hosted a field day and a Tour. On Saturday I coordinated a wedding at the farm- It was beautiful- and a lot of work. Also on Saturday I picked up four four-week-old kittens to foster from the farm across the street. And it doesn't stop there, Sunday I had three volunteers out to help with a landscaping project around the farmhouse.

I took most of Monday off and this week was a little more mellow; only one farmhouse rental to deal with, and oh yeah I got a dozen baby chicks on Wednesday. So this week I've finally been able to spend some time in my vegetable garden. Not too much- I've still got the kittens to take care of, and a number of other non-garden projects in the works. The non-garden related projects include hosting a bridal shower tea party for my friend Nina and all that that entails such as the making of invitations (last wednesday night) and the cleanup of my apartment and back porch garden (still a mess- I'll get to it one way or another).

Making strawberry jam while strawberries are in season is another current project. I tried to make a batch last night, but it didn't gel so I had to redo it this morning. It didn't taste super impressive so I got my mom to get my grandma's recipe from her(it's awesome). I guess when my mom told my Grandma that I'm canning jam, my grandma got kinda excited and sent over six cases of canning jars. Apparently she doesn't use them any more. I'll use them eventually, but in the mean time I have to store them. So I guess they're going in the back room with the fifty other cases of jars that I've got socked away.

Last but not least that brings me to garden projects. Brian is putting in irrigation lines so there are trenches all over the place and my garden looks like a war zone. Thankfully it's raining right now so it's a reprieve from the constant hand watering that we've been struggleing to keep up with. Remember how I advised not to hand water? I don't always follow my own advice so you shouldn't feel compelled to either.

More importantly in the garden, like I mentioned way back when I was talking about North Carolina, It's time to plant tomatoes in Davis, or at least it should be, but with all the cool weather (I totally missed the hot spell when I was on the east coast) I'm not sure the soil has actually broken 65 degrees yet, May 15 is the average date, but we live in times of weird weather. Soil temperature notwithstanding I planted tomatoes this week (readers-once again, keep this hard headedness in mind and consider it well when taking my advice). All gardening advice- no matter who is giving it should be taken with many, many grains of salt. There are lots of ways to do things and none of them are wrong.

I got my transplants at Morningsun Herb Farm in Vacaville. I don't start tomato, eggplant or peppers from seed anymore because I generally want one or two each of a bunch of cultivars and it's easier to get seedlings as long as the place I'm getting them from has a decent selection, and morningsun has a great selection! My tomato list so far for this year is as follows:

Aunt Ruby's German Green: The outside of these guys is pretty ugly, green with lots of brown scarring, but when you slice them open there's a pink blush in the center. Their flavor is fabulous and in my previous experience, the plants are productive and healthy.

Cherokee purple: A classic. Dark brownish purple beefsteak fruits. The flavor is sweet, smoky and complex. Not super productive in Davis, but well worth it for the flavor.

Carbon: Another "black" tomato similar to Cherokee purple, but the flavor is not quite as good. This however was my most productive plant two years ago.

Custorolee: A red french heirloom beefsteak. This cultivar yeilded the biggest, and best tasting tomato I've ever grown, or seen, or tasted for that matter. It was literally like the size of my head beautiful, red and blemish free. The caveat is that the plant only made the one fruit. The plant I had last year died before even flowering, so this one is a gamble, but worth it if it pays off.

Mariana's Peace: This is a pink potato leafed beefsteak like Brandywine, only unlike brandywine it will set fruit in the Davis summer heat. This was my best yeilding tomato last year, actually it was just about my only yeilding tomato.

Mexico: A new one for me. Supposed to be a large productive pink beefsteak.

Omar's Lebanese: Another new-to-me beefsteak

Thessaloniki: Yet another new-to-me beefsteak. I chose both this and the above because they come from hot, dry medeterranean climates so my thought is that they will do well in our dry heat.

Mr Stripely: My aunt Marilyn's favorite. I've never grown them, but they sure are great out of her garden.

Big Beef Hybrid: This is insurance in case sclerotia and nematodes strike again like they did last summer.

Aunt Gertie's Gold: These are supposed to be good and High yeilding

Roma Hybrid: I have 8 of these. They're another insurance policy so that I get some tomatos to can. I find that it doesn't matter whether the tomatoes I use for canning are heirlooms or hybrids; the cooking destroys the complexity of the flavor, so I might as well start out with something low in moisture like a roma. I think the decreased cooking time of low moisture tomatoes does more for the flavor of the finished product than anything else anyway.

If I can find them I'll plant some Amana orange- these seem to keep producing fruit much later into the fall than any other tomato plant I've experienced. I'm also toying with the idea of planting a sungold. I'm generally down on cherry tomatoes- they're too much work to harvest, but I miss snacking on them in the garden if I don't plant them.

Mmkay 'Nuf said for now. I'll hopefully add some photos later. Tata!

Tuesday, April 7, 2009

Growing Corn in the EC Garden---Mmmm Smut!

My apologies for the long post. What can I say- Corn is complicated.

Corn is the un-vegetable. It’s really a cereal crop. In my opinion it’s one of the hardest crops to grow, and not necessarily worth the effort and space that it requires, but I know that some people, like my husband, are huge corn fans and feel that no summer garden should be without it. For that reason I grow corn every year and I find lots to like about growing it: growing such tall plants feels like an accomplishment, Brian grining as he eats ear after ear right off the plant, people lavishing praise upon me when I give them fresh corn, and oh yeah, I like eating smut… more about that later.

Another cool thing about growing corn is that corn genetics are really complicated and this bears out in interesting ways when you plant different corn cultivars. You can see how much plant breeders have changed corn's genetics when you plant an heirloom sweet corn next to a modern hybrid; it’s like watching the green revolution in action. Last year I planted two corn cultivars ‘Silver Queen’, an old Open Pollinated Cultivar and ‘Bodaceous’ a modern hybrid with the sugary enhanced gene. The differences were remarkable.

Silver queen grew two feet taller than Bodacious, and the plants grew multiple side shoots, called tillers, whereas Bodacious had no tillers. Bodacious yielded earlier and consistently yielded two identical ears of corn per plant, and all the ears were ready at the same time. Silver Queen yielded one perfect ear of corn per stalk, ready first, then a second half ear a few days later, then another one or two of half ears on the tillers a couple of weeks later (many of the tiller ears developed smut!). Overall Silver Queen made a little more corn, but the plants were bigger, more raggedy looking, and the half ears weren’t all that high quality compared to the Bodacious ears.

Flavor-wise, when Silver Queen and Bodacious were eaten right off the plant, they were similar, silver queen’s kernels might have been a little thinner skinned, and the meat of the kernel (endosperm) a little firmer, but overall they were equally sweet (sweetness IMO is the single dimension of corn flavor… which may be why I’m not crazy about it). The difference between the two cultivars was much more noticeable when I took corn home and stored it a day or two before eating it. Even after a few hours off of the plant the silver queen became starchy and less sweet, while the bodacious maintained its sweetness for a few days.

Longer shelf life is a hallmark of the sugary enhanced (se) gene that Bodacious carries. There are a number of different hybrid sweet corn types with a number of different named genes that confer a number of different traits. Some of these genes are incompatible with one-another for pollination, so plants of different genotypes have to be isolated. This article,Issue7.pdf from the University of Delaware breaks down the details of sweet corn genetics, and isolation requirements better than I have the ability or desire to do.

For the average gardener in the EC garden stick with open pollinated or sugary enhanced sweet corn and make sure that they are isolated by at least 350’ from popcorn or field corn to avoid cross pollination that will make the kernels starchy. The fancier sweet corn varieties are only available from seed catalogs; most people don’t grow them so you don’t have to worry about accidentally picking up the wrong type of seed at the nursery or the wrong type of pollen coming over from somebody else’s plot.

Ok, friggin enough nerd-talk about corn genetics. Once you get past seed selection there are a number of issues I’ve run into and I’ve seen others run into growing corn. First of all, Corn is a heavy feeder. Beds need to be amended with something high in nitrogen, like manure, not so much that the plants will burn, but the high carbon low nitrogen rice hully ‘manure’ available in the garden just won’t do. The stinky green manure can work, but it will burn the plants if you use too much. Last year I used a lot of boxed organic vegetable fertilizer. It was expensive, but it worked great. This year I have a lot of high nitrogen compost, so I’m using that.

Because corn is wind pollinated it needs to be planted in a patch of at least nine plants in a circle or square, not a row so that they can pollinate each other. Keep this in mind as you are laying out your planting area. Also keep in mind that corn uses a lot of water, so hand watering is not recommended. For irrigation I’d recommend laying out T-tape or drip line in the planting area and direct sowing along the line. It is not necessary to plant corn in raised beds. In the past I’ve just turned the soil in rows and raked out narrow, shovel width, seed beds. I make my rows 36” apart, a little wider than recommended on the seed packet, for ease of harvesting (sometimes the plants get covered in aphids at the end of the season and it sucks to have to get too close when you’re harvesting). I plant seeds 4 inches apart and thin to the strongest plants 8-12 inches apart.

The minimum germination temperature for corn is 50 F and optimum temperature is 60-95 F, that means that in Davis, the window for planting corn starts at the beginning of March and goes until early June. I planted corn on Memorial Day a couple of years ago and had a great harvest in Mid September. You can plant a few plants every couple of weeks during this period to have a continuous harvest of corn throughout the late summer and fall. As with all large seeds, soak overnight before planting to aid germination.

Pests and diseases abound with corn. The first problem you will likely encounter is birds eating your seedlings. Seedlings should be netted until they are about 10” tall to prevent this. Corn grows so fast that you can almost see it getting bigger in the June heat. It’s not usually bothered by pests and diseases during this time unless it is stressed from too much or too little water or fertility.

Most of the pest and disease damage starts to occur once the ears start to form. Corn ear worms will eat the kernels near the tip of the ear, you can either poison them with Bt when the corn silks show up, or just cut the damaged part of the ear off at harvest like I do. Aphids are a problem towards the end of the season. They tend to attack the open pollinated corn after I’ve harvested the first ears. They’re less of a problem with the hybrid corn since the harvest comes all at once. I use a strong jet of water from the hose to knock down aphids, if I bother with them at all.

The most annoying pest is the rodents, rats and squirrels, which come at night, peel away the husks, and eat all the kernels off of the corn. These guys are deterred somewhat by fences, but I’ve had the best success controlling rodents in the garden by cutting down weeds and brush in surrounding abandoned plots and on domes land (with permission), thereby reducing rodent habitat. I’ve also heard people suggest planting corn early so that you harvest before the rodents have had their babies for the season and the rodent populations are low. I’ve gotten lots of good late harvests though, so this seems unnecessary at least in my area of the garden.

How do you know when to harvest corn? The first sign is when the silk sticking out of the end of the ear turns brown. Next, feel the ear of corn through the husk, it should fell nice and full. If it feels full, you can pull back the husk and pop a kernel with your finger nail, the juice that comes out should look half way between water and milk. If it is watery the ear isn’t ready. If it is very opaque the corn is starchy and past it’s prime.

When you’ve picked your corn ears and shucked them look out for any enlarged gray kernels. These kernels have been infected with a fungal disease called smut. Don’t worry, if you have these you are very lucky indeed, because smut is edible and delicious. In fact, I consider it one of the redeeming qualities of sweet corn. Cut the kernels off of a smutty ear of corn (if they’re black and smell of ammonia, they’re too old, throw them out; plump and gray is what you’re looking for) and sauté them with a little garlic, then use it to fill a quesadilla. The flavor is earthy and complex in addition to sweet… Wonderful!

Recommended Cultivars

Open Pollinated: Silver Queen, Golden Bantam

Hybrids: I haven't tested a lot of these out. Look for sugary enhanced cultivars because they're compatible with open pollinated types, they'll have the (se) symbol on the packet somewhere. Also look at the number of days to maturity. In general, the later season cultivars with the greater number of days to maturity are higher quality. Plant early season corn only if you want an earlier harvest. This year I'm trying out a number of hybrids including: Delectable, Spring Treat, and Argent. Bodacious will also make a repeat appearence.

Friday, April 3, 2009

No-Knead Bread

Not garden related, but who cares...? This is what I get to eat for lunch, and the exciting part is that I made it myself (I also grew the lilacs behind it in the picture). It's Mark Bittman's No-Knead bread. I know that I'm a little late to sing the praises of this one (the recipe was published like 2 years ago, and I do seem to recall that there was quite a cacophony of praise on the intarweb), but it took me a while to get around to making it, and it turns out that it was worth the wait. It's just like rustic bakery bread; it has the thick and crispy crust, the chewy crumb and the yeasty fermented flavor of a well heeled loaf. As far as I can tell the only difference is that instead of the familiar alcoholic bready aroma, this loaf smelled like play dough when I sliced into it. Brought me right back to pre-school. It's stupidly easy to make and delicious... I highly recommend it!
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Wednesday, April 1, 2009

Melons in the EC garden

I got an email from a fellow EC gardener asking about how to grow melons and what varieties to grow in the EC Garden. My answer is as follows. I'll try to convert the chart that I mentioned into a Google doc in order to post it. Also I'm hoping to get out to the garden and take some pictures of my newly formed garden beds(I'm still sore!) so you all can see what I mean when I talk about plant spacing and mulching. Check back soon!

Here's the semi-unsolicited melon advice:

Growing melons is surprisingly easy in the EC garden. Our climate and soil are ideal for them. The main challenges I've run into are 1) Planting when the soil is too cold 2) Critters eating my plants and 3) theft

The latter two problems can be solved with a good fence. Rabbits will go for melon vines before anything else in the garden, and melons in the garden often seem to sprout legs and walk away. I plant lots so that I still get some after all the losses.

Melons are a warm season crop and need to be planted later than almost anything else in the garden. The minimum temperature for melon seed germination is 60 F and the ideal soil temperature is 90 F for muskmelons (i.e. canutulopes and honeydews) and 95 for watermelons. I've attached a Google doc with average soil temperature from the cimis weather station 1/4 mile away from the garden so you can figure out what the soil temperature is at a given time of year in the garden.

The minimum soil temperature breaks 60 in mid April, so this is the earliest you can plant melons. You could theoretically plant a little earlier by planting in raised beds or mounds so that the soil gets a little warmer, or by starting seeds in a warm indoor location or in a greenhouse and transplant the plants outside once the soil has warmed up. I don't bother with starting seeds indoors though, because melons are easy to direct sow, and we have such a long warm growing season that waiting a little longer to plant doesn't matter, it's not like the plants are going to get frozen before you get melons in the fall. Also all cucurbits (melons, cukes, squash) are prone to transplant shock

Melons like warm soil and lots of nitrogen, so before planting I dig raised beds or mounds about 8 inches tall and amend them with manure, not the dry rice hull stuff , but a small amount of the nasty green stuff worked into the center of the mound. I soak my melon seeds overnight, then plant clusters of six seeds about 6 feet apart. You have to plant full sized watermelons more like 8 or ten feet apart with equal spread. I recommend small watermelon varieties like icebox or blacktail mountain because it takes a full plot's worth of space to grow big varieties like charelston gray (which are awesome if given space).

When the first true leaves appear, I thin to the strongest 3 plants. I usually irrigate with a drip system, one or two emitters per melon mound. Watermelons are surprisingly drought tollerent and need much less water than other melons. If you don't intend to put in a drip system, form a basin in the soil around your cluster of melon seedlings cover it with rice hull mulch to prevent surface crusting, then to provide sufficient water to the plants fill it 4 or 5 times, letting the water soak in between fillings, each time you hand water (about every other day durning the summer). Watering for all types of melons should be cut drastically when the melons reach full sizeand the rinds start hardening up to prevent splitting. It's also a good idea to put some newspaper or straw under each melon when it starts to size up to keep the underside dry an prevent damage from roly poly bugs.

My favorite melon varieties for the EC garden are:

Charantais-- A french heriloom cantulope: they tend to split open but they have the most amazing flavor
Old original: this is also known as a persian melon, I think. Crispy, very sweet white flesh. They have the seeds at Ace-- Botanical interest brand.
Stutz: seeds of change carries this one
Eel river: also a seeds of change cultivar
Crane: and heirloom from Santa Rosa, Ca. You can get the seeds from Baker Creek

Ice box: Small, Ace wil have it.
Blacktail Mountain: Another small one, and my fave for flavor. Baker creek and Sand hill Preservation have the seeds.
Charelston gray: Huge, WMV resistant and delicious. Needs a full plot's worth of space to grow.

Wednesday, March 18, 2009

GBBD -- Introducing My Back Porch Garden

Abutilon 'Mary Anne' blooming in front of my drying jeans on my back porch (I spend way too much money on plants, but I can't be parted with $1 in quarters to dry my laundry on a sunny day). This plant has been blooming continuously for like 3 years. Awesome!

Unlike most serious gardeners and garden bloggers, my impulse to garden didn't arise when I bought my first house (I'm still waiting for that). Rather, I've been gardening for as long as I can remember. I took over my family's tiny urban vegetable garden in middle school. In high school I used to cut class to go home and work in the garden. The urge to garden didn't stop when I left my parents' house either. I'm sure that there are still bulbs and asparagus plants that come up every year in the neglected patches of dirt I adopted aroud all of the places I lived in college.

This is my teeny-tiny pond as viewed from my
kitchen. The reed fencing coveres an ugly metal shed.

I'm done with school now, but I still have more or less of a student lifestyle, and my gardening is still largely unsanctioned. My husband, a grad student, and I live in an apartment building in downtown Davis that is filled with students, and we all share the back yard. That means that all summer long the space gets used for outdoor movie nights, barbecuing, drinking beer etc.; I garden in it too. It's an unlikely place for a garden, but the management turns a blind eye, the neighbors are respectful, and the mow and blow "gardeners" don't seem to do too much damage.

My pots on the back porch and two small beds are way too shady and small to fully satisfy my gardening urge, so I have to garden elsewhere too (The vegetable garden that frequently appears in my blog is in the Experimental College Community Garden on the UC Davis campus). But the back yard has some really pretty ornamentals that deserve to be shared on GBBD (or a little thereafter, I'm bad at getting things done on time). Not a whole heck of a lot is blooming right now, but I'll share more next month.

I put these violas in right before our superbowl party because the place was looking so drab. I guess it shows my prediliction is to pay more attention to plants than football.

This Corsican Hellbore is pretty amazing. I love green blossoms!
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Tuesday, March 10, 2009

Some Technical Advice about Watering

My friend Doug just asked me for technical advice on irrigation. This is what I said:

Infrequent deep watering is best. In the height of summer I water for 2 hours twice a week via drip system. This time of year(early spring), because evapotranspiration is low, 15 minutes once a week when it hasn't rained for a week is plenty. Drip systems are best because they deliver water directly to roots and soil so there is less loss from evaporation.

Hand watering isn't exactly as wasteful as sprinkler watering, but it generally isn't effective except on seed beds. You'd need to stand there and hand water for more than two hours to apply the same amount of water to your plants as a drip system. Reality Check: Hand watering for 5 minutes on 20 square feet of soil area only waters the first 2 1/4 inches of soil. That means that all the water you are applying is at the surface where it can evaporate. Also it encourages root growth at the surface where the roots are prone to drying out. Lastly the action of the falling water hitting the surface breaks down the soil particles and causes a crust to form when the soil dries out. This crust prevents the water from penetrating the next time you irrigate unless you break it up with a cultivator in between irrigations. Mulching helps with the surface crusting, but doesn't totally prevent it.

If you must hand water, make sure that your your seedbed is flat, so that water goes into the bed and doesn't run off onto the path. It is also a good idea to make a little bowl around the root zone of each transplant. If you fill a bowl around a plant 2 or 3 times during a hand watering session you can get the water deeper into the soil around that plant.

Overhead watering is so bad I can't even write a coherent paragraph about it. It just sounds like a list of problems, so that's what I wrote.

Problems with overhead watering:

  • Wasteful because a lot of water (as much a a third on a summer day) evaporates while it is flying through the air.
  • Promotes weed growth, especialy bermuda grass, because you are watering areas, like paths where you don't want weeds to grow.
  • Promotes diseases because water sitting on the leaves of plants, especialy in the warm summer months, is great for fungal and bacterial growth.
  • Causes surface crusting which impedes water penetration at the next irrigation.
  • Annoying because sprinkler spray generally doesn't stay in your plot. Overspray hitting passers by (or the toolshed!) is obnoxious.

If you are going to use sprinklers, 2 hours twice a week in high summer is a good amount of time. Please note that this uses much more than the same amount of time running a drip system because you are watering the whole surface of your plot, not just where the plants are. If you must run a sprinkler system run it just before sunrise. Watering while it is still dark minimizes evaporation, and minimizing the time that water sits on the leaves overnight reduces the risk of disease. Cultivating to break up surface crusts and mulching with rice helps prevent surface crusts.

With all that said, I have to admit that I've overhead watered my plots mostly because it is much cheaper to install sprinklers than drip. They work best on a well weeded and mulched plot where crop plants cover most of the soil surface area. The crop covering the soil shades out weeds and slows down the water drops before they hit the soil and cause surface crusting. DO NOT USE SPRINKLERS IF YOU HAVE ANY BERMUDA GRASS IN YOUR PLOT. It will go crazy if it is watered in the summer. I used sprinklers on my corn last year, and the corn did well, but what started as a tiny area of bermuda grass in the plot got totally out of control in a sunny, well watered area. Never overhead water tomatoes, eggplant, or peppers (cucurbits are pretty suceptible too). They just can't handle the disease that overhead watering causes.