Cool Weather Veggies and Greens

By Christie Withers   Master Gardener

After living in Fairbanks, Alaska for twenty years, I really appreciate the fact that I can grow many vegetables year round back here in California.  Some of my favorite varietals for my north county garden add both beauty and food to my raised beds. Kale, swiss chard, spinach and lettuces such as redleaf, romaine, and arugula, thrive throughout winter and spring and will produce before the extreme heat arrives and drives them to bolt.

Many cool weather vegetable varietals will also tolerate a short freeze, which can happen up until early April in the north county.  Be sure to read the back of seed packets for temperature tolerance of various seeds.  Cool season crops grow best and produce highest quality produce with daytime temperatures ranging from 55-75⁰F.  If you are in the south county or along the coastal zone, pick varietals for your particular micro-climate.  Garlic, leeks, onions, radishes, peas and potatoes can be planted now and will produce over the next three months.  Garlic takes very little room and leeks do well in spring and are relatively inexpensive to buy.  Onions are easiest to start if you purchase sets.

Even with the early March rains, water conservation is still a priority. Keep in mind that growing veggies in blocks, using the square-foot gardening methods, will conserve water during our intense summer months. Group vegetables with similar water needs to improve irrigation efficiency. Providing wind breaks and a thick layer of mulch will reduce evaporation and increase the soil's water holding capacity.  Be diligent about weeding as the soil warms now so they don't compete with your vegetables for soil moisture.

Do you have questions about what to plant in your garden during the drought?

Visit our educational demonstration garden - Garden of the Seven Sisters - at 2156 Sierra Way, San Luis Obispo. Our garden will be open to the public every Thursday and every third Saturday of the month from 12:00 to 2:00 p.m. UCCE Master Gardener docents will be on hand to answer questions about our many educational plots.

Please make note of the following:

• No pets allowed other than service animals
• Rain or inclement weather cancels
• For more information, call or email our
• helpline - 781-5939, or e-mail us at anrmgslo@ucanr.edu

Replenishing Rainwater Gardens

Groundwater Part 3

By Andrea Peck

If you're not careful, it will sneak up on you. Just simply mosey along any old sidewalk and sooner or later you'll walk past one. It will probably be difficult to spot this clandestine garden feature since it is camouflaged as an ordinary plant bed. But, don't be fooled – you may be looking at the super hero of water harvesting: the rainwater garden. Rainwater gardens may be hidey, but they address a multitude of water sins just by existing.

Rainwater gardens are slight depressions in the garden that are planted with a special blend of drought tolerant and water tolerant flowers or grasses that allow water to pool and soak into the ground. Often native species are well-suited for the job because they tolerate local rainwater vagaries. They also tend to grow long roots that help filter out impurities that accumulate as the water runs into the system. Generally, rainwater gardens are placed in an area that naturally has a water flow towards it. This natural element is then tweaked to pull in more water, allowing it to percolate into the soil. Rainwater gardens intercept the bad boy of the water world: runoff. Runoff can start out as pure as the driven snow, but inevitably turns into a bad apple by collecting pollution as it rolls towards streams, oceans and rivers. Runoff causes general upheaval wherever it runs, often in the form of flooding.

Creating your own rainwater garden is a possibility for the do-it-yourselfer who is willing to do a bit of planning and research. (I'll give an outline here, but for a thorough understanding it is best to research fully before taking on this project.)

You will first need to determine the size of your roof or other impermeable surface that will be feeding into the rainwater garden. A general rule of thumb is to build a rainwater garden that is 10-20% the size of the section of roof or surface that will supply the water. The garden should be built 10 to 15 feet from the foundation of your home. It should not be located near a septic tank, utilities or other structures. Make sure that you select a safe spot – water can wreak damage. Once you find an empty spot that is the right size, you must test your soil for permeability. One way to do this is to dig a hole 1 – 2 feet down and fill it with water. (During dry weather it is suggested that you fill it three times and “measure” the third dousing). Note the water depth and the time. Wait until all the water is drained, note the time again and follow this calculation:

Number of inches of water ÷ the number of hours it took to drain  =

Example:

12 inches ÷ 8 hours = 1.5 inches per hour

If your soil drains at .50 inches per hour or better, it is considered well-draining soil.

 If you had to bring out the big guns to dig the hole, or if your water is refusing to drain, you may be looking at a spot that has hard-packed soil; you may have to consider another location. Pick another spot and try the drainage test again.

Finding a good spot will be the beginning of your real work. You will have to measure off the area and dig down 8-12 inches. Also, rainwater gardens need an access point, so you will need to build that in. Many gardeners choose to create a rocky swale, reminiscent of a natural dry stream to bring the water from its source (such as the roof downspout) into the rainwater garden. The rainwater garden must also have an overflow in the event of extreme rains.

Before planting, make sure that you have good soil. Generally, you will have to amend the soil, so be prepared to dig a bit more. For well-draining soil, a mixture of 65% native soil and 35% compost is a good mix. For poor soil, 60% screened sand and 40% yard-waste compost is a good combination. Mix the soil well and maintain the 8 to 12- inch depth. Make sure that the basin of the rainwater garden is level. This will prevent pooling in an uneven fashion.

Many plants, including groundcovers, grasses, shrubs, even trees, are appropriate in the rainwater garden. Some examples include: yarrow, manzanita, hair grass, Indian paintbrush, California poppy, sage, manzanita, toyon, coffeeberry and trees, such as California bay laurel, willow and California sycamore.

When planting, leave room for ample growth and finish by mulching. Weed as necessary, water to establish plants and enjoy when rain finally drops.

For more ideas and a video of how to build a rain garden click the link below and enjoy!

https://www.youtube.com/watch?v=9Kti4HJ45BM

Photo by Terri Sonleitner Law

Water Conservation For The Vegetable Garden

By Terri Sonleitner Law  Master Gardener

Q.  I grow vegetables for my family, but I know we are in a severe drought. How can I use less water and grow tasty vegetables in my garden?  Lindsey, Atascadero.

Now is the time to implement water-wise strategies that save water while still producing a bountiful harvest. Prepare the soil by removing all weeds by the roots and amending the soil with organic matter, thereby, increasing the water holding capacity.Improving soil nutrition can increase yields without increasing water needs. Next add a heavy layer of mulch. Well mulched soil will retain moisture longer.

Consider a new planting strategy. Try planting in blocks rather than single rows to shade plant roots and reduce evaporation. Group plants with similar water needs to irrigate more efficiently. Plant reliable varieties that have produced well for you before; or, you simply plant less to save additional water.

Irrigation strategies are critical to the overall goal of water conservation. It's best to water during early mornings when the wind is calm and temperatures are cool. But most importantly, do heed any city guidelines set forth in your area. A soaker hose is the least expensive and is easy to use. Drip or trickle irrigation on timers is ideal and can reduce water usage by 50%! Either way, remember to place irrigation hoses below the mulch to further reduce evaporation and make sure your plants have easy access to this precious resource. Check soil moisture regularly to avoid over watering.  Dig down below the mulch to evaluate soil moisture. Squeeze a handful of soil in your hand.  If it holds its shape, additional irrigation can be delayed.  If the soil is dry to a depth of 4-6 inches, it's time to water.

In depth drought information resources are available at the UCCE San Luis Obispo County website: http://cesanluisobispo.ucanr.edu/Drought_Information/Vegetable_Gardens/

 Please join us for a "How to Build a Raised Bed Workshop" on Thursday March 20 at 4:00 p.m. in our demonstration garden at 2156 Sierra Way, San Luis Obispo. A raised bed can be water efficient whether planted with vegetables or drought tolerant plants. The workshop will be about an hour and building plans will be provided.

Groundwater Woes

Part 2

By Andrea Peck

I am hoping that many of you took the challenge and found out where your water is coming from. From the research that I've done, I see that the majority of us in SLO county (and the country, for that matter) get at least a smidgen of our water from groundwater sources. To top it off, if my mental scratchpad serves me correctly, I do remember reading that the majority of surface water sources (such as lakes, reservoirs, and rivers) are fed by groundwater. So, either way you look at it, you are probably using groundwater daily.

The world is comprised of 70% water, so you may wonder – what is the problem? Well, the vast majority (97.5%) of that water is ocean (salty) water that is unusable. The remaining 2.5% is fresh water. Only 1% of this available water is usable. The rest is inaccessible or just plain too dirty to drink.

That's it. That's why they call it precious.

This is important because we need to be aware that when we dispense our water it is either replenishing the groundwater or it is not.  The thing that dawned on me like a ton of bricks was that water that is on the surface tends to evaporate and water that accumulates often leads to run off.  Much of our water is not percolating back into the soil; it is floating up into the sky or sheeting off into the ocean. Yes, it may continue the water cycle by evaporation, but have you experienced our winds? Do you really think a bunch of blowy moisture is immune to being shoved over to the next continent? Plus, water that runs down roads and gutters brings nasty bits of pollution with it which impacts native wildlife and marine ecosystems.

I began to consider that this may be why the experts are continually going on about groundwater levels and water tables and the like. Though the water will end up coming back as rain through the water cycle, it may not end up on our soils or more importantly, at our tap – it may end up somewhere else.

It was kind of an “aha” moment.

The conclusion is clear: we need to keep as much water as we can on our property where it can sink down through the rocky fissures that allow our water to collect underground.

How do we do this? Well, certainly you can see that letting rain drip onto patios or driveways and then run into the street is counterproductive.

Rainwater catchment systems are probably the simplest mechanism you can install to curtail rainwater runoff – the water does not even need to be used in any particular manner – as long as it is allowed to permeate soil instead of concrete, you are increasing our chances of replacing groundwater.  Remember that familiar estimate: a 1000 square-foot home can generate 600 gallons of water during a 1” rain.

In fact, this method is so effective that many places, Los Angeles included, are considering making rainwater catchment systems mandatory in new developments.  (See link below).

There are also flexible rainwater extenders that can be moved to allow roof runoff to percolate into soil. It is important to remember that roof runoff is not appropriate for most edibles because of the particulate matter, bird feces and other detritus that comes from the roof itself, so it is best to place your water into an area that contains ornamentals. Where there is just plain dirt, try a cover of mulch to increase permeability. What the heck, while you're at it, add a drought tolerant shrubbery as a reward.

There are many methods that increase your “groundwater percolation rate.” One idea is to replace existing lawns with native or prairie-type plants. Native plants have extensive root systems that pull water in and clean it by filtering out pollutants (similar to an estuary). Lawns, on the other hand, do not have a strong water-retaining capability.

Replacing a portion of your driveway with gravel that allows water to seep down is another solution for those who are looking for a large, workout-style project.

Pavers are great replacements for patio areas because water can permeate through the connecting points.

Remember your voracious washing machine? Though there are caveats when using this water, (it cannot be stored or used on edibles) setting it up as a grey water system will replenish groundwater supplies.

The point is, the vast majority of us are using groundwater in one way or another.  Being thoughtful in regards to our use of water, along with replenishing groundwater is part of the new mindset that we as a culture need to adopt.

Check out this link to see how water catchment systems are the new home accessory:

http://www.treehugger.com/clean-water/los-angeles-may-get-mandatory-rainwater-harvesting-law.html