Tuesday, March 30, 2010

Drip Irrigation vs. Drip Irritation

    Anyone who has ever struggled with a drip irrigation system in their yard may believe that the term "irrigation" may be a misnomer. The tendency for such systems to be plagued with clogged emitters, broken pipelines and incompatible components may lead one to consider renaming this watering headache as "drip irritation".
    The biggest benefit using a drip irrigation system is that water is not wasted. The emitters can be placed directly on the plants' root zones, insuring that the plant - not the surrounding weeds - get the water. And less water wasted can translate to lower water bills.
    There is, however, a trade-off: unlike sprinkler systems, drip irrigation components, connectors, lines and emitters should be checked more often and more thoroughly to make sure the system is flowing correctly. And problems can pop up all along a drip line:

• Dirt, sand or bugs can clog the in-line filter screens, preventing water from leaving the faucet; they can clog individual emitters as well. 

• An errant mower or weed whacker may have sliced and diced your 1/2-inch or 1/4-inch pipelines as well as your emitters. 

• Connectors may have worked loose in the heat, sending water gurgling down the driveway. 

• Replacement parts may not fit correctly; so, back to the hardware store you have to go.

    If you are willing to work at it, drip irrigation can be a worthwhile investment. Some tips I've learned the hard way over the years:

• The best purchase? An inline emitter system. This half-inch poly pipe has one gallon per hour emitters built into the inside of the pipe, usually spaced 18" apart. These pressure compensating emitters flow evenly, with little if any blockage. Plus, you can't accidentally weed-whack off the emitter. Different spacings and different gph emitters are available on inline systems.
• Not all half-inch, five-eighths or three-quarter inch poly pipe is created equal; you'll find this out in a hurry when the connector doesn't slip on easily...or is too loose. Different manufacturers have different diameter pipe. For half-inch it could range in an outside diameter from .620 to .710. If you are not sure what size you have when you go shopping for more poly pipe, take one of the slip connectors from your existing system with you.

• Those connectors (slip, corners, tee's) may have different colored rings on the end for a reason: they fit on different sized half-inch pipe, specifically, Raindrip. One solution if faced with different sized mainline pipe: purchase adjustable connectors.

  • Know the difference between pipe thread and hose thread parts; otherwise, you won't get a tight fit and leaks will occur. If you're connecting to an outdoor faucet, make sure the anti-siphon valve, pressure regulator and female faucet attachment are hose thread parts. Attachments to PVC pipe parts should be pipe threaded. Usually, the letter "p" or "h" in the part's serial number is your best indication.

  • Use filter screens. Check them for debris on a regular basis. If you use y-shaped filters (which make fertilizing chores a snap), flush them out once a month.

  • If your water supply is turbid (contains dirt particles), stay away from half-gallon emitters. These are too quick to clog.

  • Remove the end cap and flush the entire system at least twice a year.

  • If you bury your 1/2-inch dripline (which can protect it from the corrosive rays of the sun), make sure you know where it's buried. Otherwise, an errant spading fork or rototiller may turn your line into Swiss cheese.

* And keep your weed whacker away from any emitters.

 Most common mistakes gardeners make when converting to drip systems:

• Incorrect watering times. Drip systems that use one gallon or two gallon per hour emitters need to run for hours at a time, not minutes. In my raised bed vegetable garden, the summer watering regimen is twice a week, six hours at a time. Your weather, soil type, slope and crops may need a slightly different watering schedule. In my 4'x20' raised beds, three inline emitter lines run the length of each bed. The lines are spaced 18" apart.

• Not enough emitters for the plant. Placing one emitter next to a new tree or shrub is not enough. Remember, plant roots tend to grow out horizontally. Emitters should be spaced evenly around the tree or shrub, in a circle, halfway between the trunk and the outer canopy of the newly installed plant. The spacing between the emitters will depend on your soil type: for sandy soils, use a 12" spacing; for heavy clay, 18-24" spacing. Add emitters towards the outer canopy of the plant as the plant grows.

• Too much water pressure. Most drip systems will work fine with just a quarter turn of the outdoor faucet, around 25 psi. Too much pressure, and you could blow out the connections and the emitters. If you have your drip system connected to your automatic sprinkler valve system, be sure to use a pressure regulator.

• Too long a run of dripline means not enough water flow. Try to keep runs of half-inch polypipe with one gallon per hour emitters spaced 18" apart to under a 100'. Bigger emitters or closer emitter spacing? Reduce the run even more. If I'm doing a long run from a faucet to the beginning of a drip area, I'll install 3/4" or 5/8" mainline poly pipe from the faucet to the beginning of the garden area, and then reduce the pipe size to the half-inch inline emitter tubing.

• Consider using microsprinklers or sprayers to thoroughly wet the root area for trees and shrubs. These put out more water, usually between 8 and 20 gallons per hour.

• Monitor the system. "Walk the lines" regularly during an irrigation cycle, making sure that all the emitters are working and there are no leaks.

Soaker hoses need maintenance, too. Flush them monthly.

A great online tutorial of drip irrigation: the Dripworks website. This site has helpful tips and videos that can help beginner and pro alike solve their drip irrigation and yard watering woes.

     The Dripworks catalog is also great resource for anyone tackling the problems associated with drip irritation...uh, irrigation. Just thumbing through the catalog can give you several "Aha!" moments for improving your own yard watering procedures.


Sunday, March 28, 2010

If Your Butt Can Take It, Then Your Veggies Can Take It

Despite the plethora of vegetable starts available throughout Northern California, late March (and early April) is still too early for many of the heat loving vegetables to be thrust into the ground, unprotected. Soil temperatures in the area are still in the mid-50's, too cold for tomato and pepper plants to put on any active growth. And the less active the growth cycle, the less ability the plant has to stave off insect and disease problems.

One way to determine the best time to plant your summer vegetable garden:

Sit in the garden bed for 60 seconds. If you can stay there, comfortably, go ahead and plant.
Some tips:
• Build a tall fence or plant tall shrubs first.
• Have a hose ready.

For the fearful and fenceless among you, get a soil thermometer.


Average Soil Temperatures/2009/Mid-Month Readings
Four-Station Valley Averages (Sacramento, San Joaquin, Yolo, Sutter Counties)

(Soil temperature readings (F) taken 6" deep)
January: 46
February: 49
March: 52
April: 58
May: 64
June: 68
July: 74
August: 73
September: 70
October: 62
November: 57
December: 45

Thursday, March 11, 2010

Terrific Tomato Tips

If this is the year for you to grow terrific tomatoes, follow these tips:
Choose suitable varieties. California's Central Valley weather is most noted for its hot, dry summers. 
Lemon Boy
Good choices for this climate include Ace, Ace 55, Better Boy, Burpee VF Hybrid, Celebrity, Lemon Boy and Early Girl (all main season tomatoes).


Beefmaster, Big Beef, Supersteak and Whopper (big-fruit varieties).

Viva Italia
Juliet, Roma VF, Viva Italia and San Marzano (paste tomatoes).

Sun Gold

 Patio Hybrid, Sweet 100, Sweet Million, Sun Gold and Sun Sugar (small-fruit varieties). 

All of these varieties were taste test favorites, in trials conducted by the Master Gardeners of Sacramento County and here at Hoffman Gardens. 

Heirloom tomatoes, varieties that were around before the 1950's, are gaining popularity. Although they may not have the built in disease resistance or high production of modern hybrid varieties, they make up for it...with outstanding taste! 
Among the heirloom varieties you might want to try: Brandywine, Old Brooks, Arkansas Traveler, Dad's Mug, Anna Russian, Aunt Ginny's Purple, Dr. Lyle, Dr. Neal, German, German Johnson, Mortgage Lifter, Pruden's Purple and 1884.

Among my favorite heirloom tomato varieties:
Kellogg's Breakfast
Dr. Wyche

Costaluto Genovese
Marianna's Peace
Zapotec Pleated

Bloody Butcher


Catalog seed sources include the Tomato Growers Supply Company  and Totally Tomatoes.

Using home-saved tomato seeds. If you want to save seeds of a particular tomato variety, remember that many varieties are hybrids; they may not necessarily come back with the same traits as the tomato you enjoyed last season. Open pollinated or heirloom tomato seeds are fine for saving, as long as they are grown at least 30 feet away from any other varieties.  For best results: save the seeds from tomatoes that are overly ripe; rinse off as much of the flesh and protective gelatinous coating from the seeds as is possible. Then, soak the seeds in a jar of water for a couple of days to remove the rest of the coating. The seeds will sink to the bottom, the gel will float. Discard the gel, remove the seeds and let dry on a paper towel. Then, store in an airtight container in a cool, dry location.

Start seeds early. January and February are the best months for starting tomato seeds; March is OK. This will allow 8-12 weeks for the plant to get off to a good start in a warm, sunny place, such as a south or west facing window. It usually takes 7-14 days to germinate tomato seeds. To test for viable seed that you've been saving: moisten a coffee filter, and place a few seeds in the filter, with space between the seeds. Place the filter in an old yogurt container, cover it, and place in an area out of direct heat. Check every few days to see if seeds have sprouted.

Give seeds a healthy start.
Use a light, quick-draining potting mix. Commercial seed-starting potting mixes are available; or, mix your own, using 4 parts compost, 2 parts peat moss, and 1 part each of vermiculite and perlite. Any small container with drainage is OK for starting tomato seeds. Fill containers about 3/4 to the top with the potting mix. Water, let drain. Plant seeds shallow, no deeper than 1/4 of an inch. To hasten germination, use a heating pad designed for seeds, such as a propagation mat. This will warm the soil to 70-75 degrees, which tomatoes need to germinate. Keep the soil mix moist. To prevent emerging seedlings from bending too much toward the sunny window, rotate the pots a quarter turn each day. If you are using grow lights, position the seedlings about 6 inches from the light source; keep the lights on 15-18 hours a day.

Movin' on up. When two or three sets of true leaves develop on the tomato seedling, you can transplant it to a bigger pot. This is especially helpful if you started your seeds in a flat or in a small peat pot, or the young stems are bending toward the light at a sharp angle. When transplanting to a bigger pot (preferably a 4-6 inch pot, but no larger than a one gallon container), prepare the new pot the same as before. However, don't fill the pot as full. Place the tomato seedling, with as much of the original soil as possible to avoid disturbing the roots, into a 1/3 to 1/2 filled pot. Then, add moistened soil mix all along the stem, up to the bottom set of leaves. If you are growing tomato seedlings in a flat, thin them out so that there are six inches between plants. This will lessen the chance of root entanglement and damping off, a fungus disease that kills young seedlings.

Timing is everything. Acclimate any indoor-grown tomato seedlings slowly to their new outdoor home; this lessens the shock to the plant, allowing it to grow at a quicker pace. About 10 days before setting out into its permanent garden home, place out during the day in a shady or semi-shady location; bring plants in at night.
Wall O' Water
Mid-Spring is Tomato Planting Time. Plant tomato transplants when the soil has warmed enough to keep the plant actively growing. In most of California, late April or early May is the optimum time to set tomato plants outdoors, unprotected, in a garden area that gets full sun. If you can't wait that long, protect those tender young plants with hot caps, row covers or "Walls of Water" - plastic, cone shaped enclosures that are filled with water which collect heat during the day, slowly releasing the heat at night.

Plant deeply. Place the tomato deep into the soil, clipping off the lower leaves and leaving only the top leaves and branches exposed. This will cause more roots to develop along the stem, speeding development.

Mulch? Yep! Surrounding your tomato plants with three inches of an organic mulch beneath the plants helps moderate soil temperature, reduces water evaporation, controls weeds and helps to feed the soil as it breaks down. Some gardeners use red plastic mulch beneath their tomato plants. A couple of university studies have shown that this can produce an earlier, bigger crop of tomatoes. Other studies indicate that the reduction of light spectrum that results with the use of red plastic mulch may stress the plant into producing most of its fruit earlier in the season, with reduced production in the late season. Your call.

Stake, stake, stake. Supported tomato plants produce more fruit and are subject to fewer problems. One of the best tomato support systems that can be used repeatedly for a number of years include "cages" made from concrete reinforcement wire. A  50-foot roll of this six-inch mesh, five feet-high wire can be cut to make about a half dozen tomato cages, each with a diameter of two to three feet. The six inch mesh allows for easy access at picking time. Stake and tie the cages to the ground, with one stake on either side of the cage.

Water carefully. Tomato plants like water on a regular basis, deeply, once or twice a week. Soaker hoses or drip irrigation work best. Regularly scheduled deep watering reduces plant stress, one of the causes for that mushy, black or brown discoloration on the bottom of tomatoes, called blossom end rot.

Fertilize regularly, but sparingly. Lightly feed the plants every other week with a balanced fertilizer (10-10-10 or less, for example). Use half the recommended dosage.

Pick, pick, pick. Don't let the fruit overripe on the vine; pick when fully firm and red. Hand picking is also the most potent control for mature tomato worms. If using chemical products, make sure the label states that hornworms are controlled by the product. Also available for hornworm control: a bacterial insecticide containing Bacillus thuringiensis (Bt). If you spot a tomato horn worm with a patch of white on its back, let it be. Those patches of white are the eggs of the parasitic trichogramma wasp that eventually will do the dirty work, eating away at the host tomato worm.
The Tomato Dictionary.

Determinate: Tomato plants whose vines make little or no growth once fruit is set. Most of the fruit develops at the same time. A desirable trait for those wishing to can or process their crop. 

Indeterminate: Vines keep producing new shoots, blossoms and fruit throughout the growing season. 

V: A tomato variety with this letter listed after the name is resistant or tolerant to verticillium wilt. 

F: Tolerance to fusarium wilt. 

N: Nematode resistance.

T: resistance to tobacco mosaic virus. 

Tuesday, March 9, 2010

Why Your Daffodils May Not Be Blooming

      From the garden e-mailbag, Joe wants to know: "I  planted daffodils years ago and most have come up and flowered. Others didn't have a flower this year. Do I consider these no longer 'flowerable' and dispose of them?"

     Many times, daffodils won't flower if they were cut down prematurely the previous spring. Always wait until the leaves turn completely yellow before removing the leaves. This is about six weeks after flowering.  If it doesn't rain, make sure those daffodils still get irrigation until the leaves are yellow. The good news: you can leave those daffodils in the ground year round.

Those non-performing daffodils may be just too darn crowded and are not getting enough food and water. If it is part of a large clump of daffodils that have ceased to bloom, it's time to separate them. 

When the foliage turns brown, dig and separate the bulbs. Replant them immediately, six inches apart and about six inches deep. Or, you can dry the bulbs in the shade, store them in mesh bags, and replant the bulbs in the Fall.

The American Daffodil Society also offers these other tips on why daffodils cease to bloom:

• Bulbs have not been fed in a couple of years. Broadcast a 5-10-10 fertilizer when leaves emerge, and again at bloom is a reasonable feeding schedule. 

(I prefer to feed blooming annuals, perennials and bulbs with a lower dosage organic fertilizer, such as this 3-7-4 formulation).


• Feeding has been with a high-nitrogen fertilizer. This encourages production of leaves, but seems to quell the plant's need for flowers.

• Bulbs are planted in a shady area. Daffodils need a half-day of sun at least to produce flowers.

• Bulbs are in competition for food with other plants. Planting under evergreen trees or with other fast-growing plants limits the food they can get. Result: weak plants and no flowers.

• Daffodils love water but must have good drainage. They do not do well where the water puddles, increasing their susceptibility to basal rot fungus. A stem cross-section that looks like this picture may be basal rot. A healthy stem is white. Basal rot is incurable; dig and discard the bulbs.

• Bulbs may be stressed from transplanting. Some varieties seem to skip a year of blooming if dug and replanted in a different environment.

• Some varieties bought from a grower in one climate may have a difficult period of adjustment to a vastly different climate. They may bloom the first year off the previous year's bulb, but then be unable to adequately build a flower for the following year.

• The bulbs may have a virus. Over time, an infected plant loses its vigor, puts up smaller, weakened leaves and stems, stops blooming, and finally dies. Dig and throw away the bulbs.

• Growing conditions the previous spring may have been inhospitable and the reformation of the bulb was affected. An early heat wave may have shut down bulb rebuilding before it was complete. The bulbs may have be grown in a smallish pot without adequate feeding or protection from heat and cold.

• Never buy or plant a "soft" bulb. Retail bulbs typically remain in closed crates for a lengthy period of time during shipping. These humid conditions are near-perfect for the proliferation of fungus diseases such as basal rot or fusarium.