By Brent McGhie, Butte County Master Gardener, May 22, 2015
As the drought continues and the need to conserve water increases, some of us are eliminating our vegetable gardens this year. However, if vegetable gardening is a necessity for you, it is possible to significantly reduce water use in the garden.
Before planting a single seed, a good first step in vegetable gardening is to amend the soil with compost. Compost adds organic material to the soil, improving the soil's water environment. Organic matter improves the water-holding ability of sandy soils and loosens clay soils, promoting better water absorption. And as organic substances break down, nutrients are released into the soil.
Mulch, mulch, mulch! Mulching is probably the single most important thing a gardener can do to reduce water consumption in a vegetable garden, or the home landscape in general. Mulching reduces evaporation from the soil by up to 35% and can significantly cut irrigation needs. Mulches also smother weeds, which compete with vegetables for water.
Grass clippings make excellent mulch because they release nitrogen into the soil as they break down. To avoid matting, clippings should applied in thin layers between one-quarter and one-half an inch deep and be allowed to dry out between layers. Do not use grass clippings from lawns that have been treated with herbicides. Other organic mulches include wood shavings, compost, bark, straw, or alfalfa. Organic mulches should be one to three inches thick in vegetable gardens; the larger the mulch particles, the thicker the mulch needs to be. Also, thicker layers of shavings, straw, or bark may lead to a carbon-nitrogen imbalance in the soil. A layer of newspaper two sheets thick can be placed under organic mulches to enhance their effectiveness. (Do not use glossy printed material for this purpose, as the ink may be toxic to plants.)
When deciding which vegetables to plant, be aware that the amount of water needed by different crops varies. Corn and most beans require the greatest water use of commonly-planted garden vegetables. Vegetables that are more drought tolerant include chard, black-eyed peas (cowpeas), heat-tolerant tomatoes (including many cherry varieties), some varieties of okra, mustard greens, eggplant, jalapeno and poblano peppers, Black Knight zucchini, and New Zealand and Malabar spinach. Shallow-rooted crops, including potatoes, onions (and most other bulb, root or tuber crops), celery, and plants in the cabbage family, require more frequent irrigation. For this reason, mulch is especially beneficial for shallow-rooted crops. Tomatoes, sweet potatoes, melons and asparagus are more deep-rooted and can tolerate longer periods without irrigation. Beans, carrots, peppers, summer squash and cucumbers are intermediate in root depth. Additionally, low-growing plants and plants with smaller leaves tend to lose less water through their leaves than taller, leafier varieties. Bush beans, for example, use less water than pole beans. Also, miniature varieties of vegetables, such as mini bell peppers and eggplants, need less water for fruit development than standard varieties.
In addition to planting less thirsty varieties, garden design can improve water efficiency. Rather than using traditional rows, plant vegetables in blocks. This creates shade and reduces evaporation. Group plants with similar water needs together (this technique is called hydrozoning). Zucchinis, cucumbers and squash, for example, require similar water applications. They can be planted in the same bed; or planted in different locations, but served by the same valve or drip line. If the garden is in a windy, breezy location, a windbreak will also reduce evaporation.
How a garden is irrigated can affect how much water it uses. Water early in the morning, so that water has a better chance to soak into the soil before it evaporates. A drip system (under mulch) is an efficient way to deliver water to crops with minimal evaporation loss. To avoid overwatering, monitor soil moisture. Generally, if garden soil has dried out to a depth of two to four inches, it's time to water. Including a timer as part of an irrigation system will reduce waste due to human error. Overhead sprinklers and hose-end sprayers are inefficient, result in high evaporation losses and are more likely to trigger diseases such as mildew. Also, the amount of water needed by plants varies over their life cycle. As a rule of thumb, water is most critical for plants during the first few weeks of development, immediately following transplanting, and during flowering and fruit production. Target the timing and amount of water with these plant needs in mind. It is also important to check and maintain your irrigation system frequently to keep it performing at top efficiency.
Water can be “harvested” from inside the house for use in the garden. For example, save your cooking water, or capture water flowing from sinks and showers before the water is hot. Wastewater from an aquarium can be reused and it will also provide a variety of nutrients for garden plants. Finally, gardens can be irrigated with graywater (drain water from sinks, showers and tubs). Before undertaking this step, check with your local public health department. The Butte County Public Health website, for example, contains a great deal of information about the use of graywater, including a link to the San Francisco Graywater Design Manual.
By Butte County Master Gardeners, June 5, 2015
The guide also includes a garden journal organized from spring through winter with space to keep track of your own garden over three years. You may want to keep track here of new plants, bloom dates, frost dates, average temperatures, pests and beneficial insects observed, and other types of practical information. Keeping a journal from year to year encourages successful gardening: creating a history of plants and gardening practices that were successful encourages you to continue with them; while noting which ones did not work well prevents you from repeating those mistakes. The journal pages provide ample space for adding sketches or photographs of your garden areas over the course of the year, as well.
Each seasonal section in the Gardening Guide and Three-Year Garden Journal includes a list of produce harvested during that period, alongside a list of tasks and suggestions for garden preparation. Each month includes a specific list of gardening tasks and tips for planting, maintaining the garden, and dealing with garden and orchard pests and diseases. Each month also features a native plant that is at its best in terms of blooms or foliage at that time -- helpful for those who plan to add more native plants to their gardens.
The appendix section includes several useful charts and diagrams, including vegetable planting guides geared specifically for the Chico area and the foothills; detailed information on caring for fruit and nut trees in our area; varieties of fruit trees that are resistant or susceptible to disease; and illustrated charts of common garden pests and beneficial insects.
The idea for the Butte County Gardening Guide and Three-Year Garden Journal arose from our experience in producing a yearly garden calendar from 2011 - 2014. The calendars were popular and we had many repeat customers every year. But we learned that most customers did not actually use the calendars as calendars; instead they turned to the gardening information, keeping the calendars permanently for reference as part of their garden library.
This discovery led us to develop a garden guide worthy of a garden reference guide. We incorporated into it ample space for garden journaling, because we have found that our own gardens improve dramatically when we keep a garden journal. Our Gardening Guide and Three-Year Garden Journal is designed with spiral binding so it will lay flat and can easily be written in without breaking the binding.
The guide costs $25 (including tax) and will be sold at Master Gardener booths at farmers markets in the area and other public events where we have a booth; at all of our workshops or talks where selling is permitted; and at the Patrick Ranch Museum gift shop, right next to our Demonstration Gardens. For information on Butte County Master Gardener public talks and workshops, please see our website at ucanr.edu/sites/bcmg.
If you liked the Butte County Master Gardeners' calendars, you will love the new Gardening Guide and Three Year Garden Journal. It has been designed, written and edited by local Master Gardener volunteers, with multiple contributions by JosephConnell, FarmAdvisor Emeritus, Butte County Cooperative Extension. The guide features cover and full-page illustrations by local artist ChrisFicken and has been printed locally by Graphic Fox. Proceeds from the sale of this publication will support the Master Gardeners' Demonstration Gardens and public education programs.
By John Smith, Butte County Master Gardener, June 19, 2015
To check your water usage, first locate your meter. Bring a screwdriver, a flashlight, and pen and paper with you. Use the screwdriver (or similar lever-type tool) to wedge into the slot on the “lid” over the meter, and lift it off; then shine the flashlight inside to make sure no black widows or other dangerous creatures are lurking in there. You will probably have to brush some debris off the face of the meter. When you do, you will be looking at a large circular dial, a smaller blue dial, and, below them both, a series of numbers. Write those numbers down. This is the base you will begin with. Once you have those numbers, you can start to calculate your daily water consumption.
Each full number in front of the decimal point on that gauge represents one unit which is 1Ccf or 748 gallons of water. The numbers to the right of the decimal point are in 1/100s (one-one-hundreths) of 748. The larger dial moves clockwise, indicating water use up to 748 gallons; when that number is reached, the full number on the gauge increases by one. The smaller blue dial indicates that water is being used at that moment. If all of your water is shut off, the blue dial should not be moving. If it is, you have a water leak or water on somewhere on your property.
There are several ways to use this information to become a more informed water user and to reduce overall water consumption.
- If you note down the water gauge number late on a night when you are not irrigating, then check the gauge again in the morning, you should be able to tell if you have a water leak somewhere on your property. –If the gauge tells you that water has been used when you have not, to your knowledge, used any water, somehow water is leaking out.
- Test how much water you actually use when hand watering with a hose. It certainly seems like hand watering uses much less water than sprinklers – but does it really? Check the number on your water meter, then, using a stop watch, see how much water you actually use in one minute with the hose on full force. Or see how many seconds it takes to fill up a five-gallon bucket watering can.
- Check that water meter number, then take your usual shower, and check that number afterwards. Subtract the smaller number from the larger and multiply that decimal number times 748. Your answer will be the number of gallons used.
- If you have an automatic watering system, record your pre and post irrigation meter readings, then use procedure above to calculate gallons of water used each time your irrigation system runs.
Those living in the Paradise Irrigation District (PID) have access to a more advanced individual water-usage information system than those with Cal Water. The water meters of PID customers are green (easy to spot). A system known as "Aqua Hawk Alerting" reports water use every hour on the hour. This information is updated online every 24 hours. PID customers can log in online to view their previous day's water use. This system allows users to look at a daily water use graph which is helpful in evaluating the effect of their water-saving strategies. Aqua Hawk will notify customers by phone, text, or email if it detects a possible leak. This system also allows customers to specify an amount of water (in gallons) or an estimated bill amount (in dollars) that they don't want to exceed. If water consumption or bill amount exceeds or is projected to exceed the threshold value,AquaHawk will send a notification. This is very helpful in meeting water budgets.
Cal Water has not adopted this reporting technology, but by logging in their account number online, Cal Water customers can view graphs of their monthly water usage, comparing 2013 and 2014 usage with the newly-reduced monthly targets.
Lawn Removal Advice
By Eve Werner, Butte County Master Gardener
California Water Service is offering rebates for those in single-family residences who remove lawn and replace it with drought-tolerant plants. This is a great opportunity—it is not difficult to realize landscape water savings of over 80% through careful plant selection, site preparation, and accurate application of irrigation. .
However, the current rules for the rebate require that homeowners complete their lawn removal project within 120 days of gaining approval to start work. Please note that four months is not enough time to properly kill many Chico lawns, especially those which contain Bermuda grass. If the lawn replacement project is started during the summer, the time restriction on the rebate forces replanting during our hot season, which can result in the stress or death of the new plantings.
The optimum time to plant a dry garden is between November, when the first rains begin to fall, and February. Planting during that period gives plants a chance to establish roots before the summer heat arrives, and before the soil begins to dry out.
In the meantime, you can properly kill your lawn. Our next Real Dirt column will explain how to do just that.
By Eve Werner, Butte County Master Gardener, July 3, 2015
California Water Service is currently offering rebates of up to $1000 for lawn removal and replacement with drought-tolerant plants in single-family residences. It's not difficult to realize landscape water savings of over 80% through careful plant selection and site preparation, and accurate application of irrigation according to the plants' actual needs.
If you plan to undertake a lawn replacement, make sure you do it properly; incompletely killed grass can regrow amid new plantings, ruining the appearance of your new landscape and creating a maintenance nightmare. The following three steps will lead to success.
Step One: observe and plan. What existing trees and plants do you want to keep or remove? What are the sun and shade patterns within your yard? What types of grass grow in your lawn? Do you want any additional amenities, such as paving or a shade structure? How will you irrigate your new plants?
Step Two: kill your lawn. Homeowners can use two eco-friendly methods to kill their lawns: Solarizing or Sheet Mulching (also below).
Solarizing uses the sun's radiation to kill lawn grasses as well as many common annual weeds, harmful soil microbes, and seeds down to a depth of 4 to 12 inches in six weeks. Most beneficial microbes survive, including earthworms. Solarizing requires six hours per day of full summer sun and takes 4 to 6 weeks to complete. It works best on fescue, ryegrass, and bluegrass, with partial success on Bermuda grass. Solarizing must be completed before new plants are installed.
Sheet mulching kills weeds by starving them of light. It takes 6 to 10 months and can be started any time of the year as long as at least three months of growing season are included. Sheet mulching works in sun or shade, and is effective on all grasses, including Bermuda grass, and many annual and perennial weeds. It is left in place permanently; over time, the dead lawn, sheeting, and mulch will break down into soil-enriching compost. Sheet mulching should be placed before new plants are installed if being used alone to kill lawn or weeds. It can be placed after plants are installed if solarizing has been completed first. New hardscape and irrigation should be installed before commencing solarizing or sheet mulching.
A third option for lawn removal is to dig or scrape out the lawn. Be warned, however, that this method will not kill Bermuda grass and most perennial weeds, which have deep roots that will re-sprout. If you choose to dig out your Bermuda grass lawn, be sure to follow up with sheet mulching to prevent aggressive regrowth of the grass.
Step Three: replant. Whichever method you choose to kill your lawn, time implementation so that you are ready to replant in the fall, winter, or early spring. The cool temperatures and moist soils of our wet season allow drought tolerant plants to develop the healthy roots they need to thrive with little water during the heat of summer. Taking time to thoroughly kill the grass and waiting until the climate conditions are suitable for new plants will ensure the long-term success of a lawn replacement project.
For additional information about the CalWater turf replacement rebate, visit their website at www.calwater.com.
Photo credits: Eve Werner
Sheet Mulching, By Eve Werner, Butte County Master Gardener
Sheet mulching, also known as sheet composting, kills weeds by starving them of light. Dead plant material will break down into compost to enrich the soil. New weeds are reduced because it is difficult for them to anchor their roots in deep mulch. The sheeting and the mulch will break down over time, forming compost. Sheet mulching should be placed before new plants are installed if being used to kill lawn or weeds. It can be placed after plants are installed if other weed removal techniques such as solarizing have been completed first.
Materials:
- Newspaper or plain cardboard. Don't use glossy colored pages as they may contain metal pigments.
- Water from a hose with a spray attachment.
- Compost or worm castings in a 1-2” layer. Quantity calculation for mulch is: (Area in square feet) x .08 to .15 ÷ 27 = cubic yards of compost required. Note, if you are replanting with native CA plants, you can omit this step.
- Wood chip mulch in a 4”-6” layer. ‘Walk-on' bark, has longish strips of wood and barks that knit together to help it stay in place. Shredded wood/barkmayalsobeavailablethrougharborists for much less cost; verify with the supplier that it is disease free.
- Quantity calculation for mulch is: (Area in square feet x .33 to .5) ÷ 27 = cubic yards of mulch required.
Process
- Scalp your lawn or weedy area with mower set at lowest setting. Remove grass/weed clippings.
- Water the soil thoroughly. To prevent runoff, you may have to apply water for a short period, wait for it to soak in, and then repeat as needed.
- To reduce spillage of mulch onto adjacent paving, dig a shallow beveled trench along any edges that are bordered by paving. See drawing, below.
- Spread 1-2” depth of compost or worm castings over entire area.
- On a windless day, place newspaper (about 5-8 sheets thickness) or cardboard over grass to be killed, overlapping like shingles. Make sure there or no gaps or holes. Lightly sprinkle newspaper with water as you go to prevent it from blowing away. Once wet, the paper will easily tear; be careful when walking on it. If it tears, place additional newspaper over the hole.
- If you are laying the sheeting around existing plants, keep the paper a foot from the plant stem, further for plants that spread by underground stems.
- As you are laying the paper, place wood mulch over the top of the paper to a 4”-6” depth. Place the mulch as you lay the paper so you don't have to walk on/tear the wet paper. If you are placing the mulch when the plants are already in the ground, keep the mulch a foot from the plant stem.
- Sheet mulching requires 6-10 months to kill a lawn. It can be left in place permanently.
- To plant with sheet mulching in place, push back the mulch and cut away paper sheeting in a circle wide enough to dig your hole. Dig the planting hole 2x the width and 1x the depth of the plant root ball. Loosen coiled roots and place the plant in the soil so that the top of the root ball is slightly above the adjacent soil. Back fill with soil from hole, forming a slight rim at the edge of the planting hole. Replace mulch, keeping it 8” from the plant stems.
Sheet Mulching in Progress
Beveled trench along the sidewalk, newspaper layered 5-8 sheets thick, and an initial layer of wood chip mulch.
Beveled Trench Diagram
- Author: Jeanette Alosi
By Brent McGhie, Butte County Master Gardener, July 17, 2015
On good sites with deeper soils and available moisture, blue oaks can't compete with other trees, such as live oaks. They are, however, superbly adapted to the shallow, rocky soils of the hot, dry foothills, where other oaks would struggle to survive. These trees can tolerate temperatures above 100° for several weeks at a time. In addition to an extensive system of lateral feeder roots, which are fairly shallow, blue oaks develop deep sinker roots, which can grow through cracks in rocks to as deep as 80 feet in pursuit of groundwater.
Normally blue oaks are winter-deciduous, dropping their leaves in the fall. However, when water becomes too scarce, even for blue oaks, they become drought-deciduous and simply drop their leaves and remain dormant until the following spring. Drought dormancy is common among desert and chaparral plants, but is a rare feature for oaks and for trees in general.
For homeowners who are lucky enough to have blue oaks growing on their land, this means “fall” may come as early as July or August in dry years. In fact, it has been noted that this year the leaves of some blue oaks in the Butte County foothills are already beginning to turn brown. These trees may look like they are dying or dead, but don't be fooled into cutting them down. They will normally produce a fall crop of acorns from stored food and then follow up with new leaves in the spring.
A tree owner may be tempted to water drought-stressed oaks, but should avoid doing so. Summer irrigation will encourage “oak root rot” and other soil pathogens and could very likely do far more harm than good. Our blue oaks have survived many droughts before this one. Keep in mind that the key to living with oaks is to disturb them as little as possible.
