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Disease Tomato Fusarium Wilt Fungi Resistant

You may have had your own tears, and understandably so. Late Blight of potatoes and tomatoes was the disease responsible for the Irish potato famine in the mid-nineteenth century. Spores are spread by rain/watering splash, insects, and wind, and through our hands and tools and through these mediums they can travel distances. Spore spread is most rapid during conditions of high moisture, marine layer days, and moderate temperatures, 60°-80°F.  Once established, the fungi can over-winter in your garden soil, on debris and weeds.

Fusarium Wilt is commonly found throughout the United States, is a soil-borne pathogen. Plants susceptible to Fusarium Wilt are cucumber, potato, tomato, eggplant, pepper and beans. Fusarium wilt causes foliage to yellow, brown spots on leaves, leaves to curve the length of the leaf, wilt, then turn brown and die. Your plants become stunted because they can no longer function properly.

The list of plants susceptible to Verticillium Wilt is impressive. You might have thought it was just tomatoes, but look: Peanut, Horseradish, Rutabaga, Cabbage, Brussels sprouts, Pepper, Safflower, Hemp, Watermelon, citron Cantaloupe, honey dew, Pumpkin, Cotton, Okra, Mint, Radish, Rhubarb, Castor bean, Eggplant, Potato, Spinach, New Zealand spinach, SaIsify, Yard-long bean, Cowpea! Cucumber, tomatoes and strawberries are particularly susceptible.

Verticillium wilt is most active in humid climates. Cool nights and moist conditions, the kind that favors peas, tend to encourage it. It lives in the soil, entering plants through the roots and is drawn up to stems, leaves and fruit through water uptake. At the same time, it is robbing the plant of moisture. The first symptoms of verticillium are usually seen in wilting, yellowing and curling leaves. Discolored streaks are often seen in strawberry stems and runners, and in berry canes.

To determine if a plant is infected with bacterial wilt, press together two freshly cut sections of a stem and slowly pull them apart. If a “stringy” sap (bacterial growth and associated resins) extends between the cut ends, the plant has bacterial wilt.

Especially Tomatoes! And of those, Heirlooms are particularly susceptible to the wilts. Instead, get varieties that have VFN or VF on the tag at the nursery. The V is for Verticillium, the F Fusarium wilt, N nematodes. Ace, Early Girl, Champion, Celebrity, are some that are wilt resistant/tolerant. In these drought conditions, consider getting only indeterminates. In the Mother Earth News tomato survey, they found gardeners chose heirlooms over hybrids if their soil is wilt/blight free. Otherwise, the longer the gardener has gardened, they more they chose wilt resistant toms if their soil has the fungi.

Western striped cucumber beetles are deadly to cucumbers. They are referred to as ‘plant-wounding insects’ and also transmit bacterial wilt. Feeding on blossoms and leaves, they carry the wilts and also spread it among squash, melons, and pumpkins. Cucumber beetles also vector viruses such as cucumber mosaic but do so much less efficiently than aphids. Spiders are one of the predators that eat the beetles. Let those spiders live! A tachinid fly and a braconid parasitoid wasp parasitize them. Grow plenty of flowers for these beneficial insects!

Radish have become my new religion! Radish repel the beetles! You do have to plant your radish ahead of installing your transplants or have it up before the seedlings start growing from seed. Grow your radish companion along where you will let the vine travel. The part of the vine growing up over an arch won’t be helped, so if you have space and infected soil, you may opt to keep your vines on the ground. Plant enough radish so you can eat some, but let  some grow out so the whole plant is big and protecting your cukes and other vines. Broccoli also repel cucumber beetles. Grow cucumbers under over summering Broccoli. Put in plenty of straw mulch to keep the brocs cool and the cukes off the ground. Whenever you see these beetles don’t fall for how cute they are. Squish.
Transplant rather than direct seed! Tiny seedlings are most susceptible to cucumber beetle feeding damage and to bacterial wilts.

Washington State Extension says:

Apply straw mulch! Straw mulch can help reduce cucumber beetle problems in at least 3 different ways. First, mulch might directly slow beetle movement from one plant to another. Second, the mulch provides refuge for wolf spiders and other predators from hot and dry conditions, helping predator conservation. Third, the straw mulch is food for springtails and other insects that eat decaying plant material; these decomposers are important non-pest prey for spiders, helping to further build spider numbers. It is important that straw mulch does not contain weed seeds and to make certain that it does not contain herbicide residues which can take years to fully break down.

Cucumber Beetles have their preferences! Bitter is their favorite. Not interested in watermelon at all, but watermelon does get the wilts, just from other sources! Anyway, see more details and rankings of varieties of different kinds of veggies. Varieties make a huge difference.

Special Planting and growing tips! 

  • Regarding soil fungi like Fusarium and Verticillium wilts/fungi, how you care for cukes and toms is super important! Cucumbers are even more susceptible than tomatoes to the wilts fungi, die pretty instantly, in about 3 days, if they get infected. So when you plant them, treat them similarly to your tomatoes if you have wilts fungi in your garden.
  • Plant cukes and toms on a raised mound/basin with the bottom of the basin above the regular soil level. This allows good drainage. Top that with a 1/2″ of compost, cover that with only 1″ of straw to let in air and sun to dry the soil. Keep the LEAVES OFF THE GROUND from the get go. Leaves touching the soil is the main way toms get the wilts. Remove lower leaves that might touch soil when weighted with dew or water from watering. Keep a regular watch for new foliage at ground level and remove it. AVOID WATER SPLASH when watering at ground level. The fuzzy damp leaves of toms and eggplant are perfect fungi habitat.
  • When they are about a foot tall, water neighboring plants, but not your toms.  That keeps the soil drier near your plant, so the fungi can’t thrive there. Since toms have a deep taproot, they will get plenty of water from what you give neighboring plants. Water near them but not at them or on them. In fact there are farmers who dry farm tomatoes! Read more!
  • If you are comingling beans with cukes lower along a trellis, plant the beans between the raised cucumber mounds. Beans don’t get the wilts, but love the water, so lower is good. They are a big plant with continuous high production and short roots that need to be kept moist. Mulch ASAP with straw under cukes to keep leaves and fruit off the ground, and out of the insect zone. Put a stake in the middle of the basin so you know where to water when the leaves get dense. Water gently below the leaves at ground level, no splash. Keep those leaves dry. When your plant gets bigger you can remove lower leaves.
  • Since the fungi are airborne as well as soil borne, plant in different places as far apart as possible. Plant so leaves of one plant are not touching another plant. Remove sickened foliage ASAP to reduce fungi population and slow spreading. Prune on hot, dry, unwindy days, mid morning to midday, after dew has dried, so cuts can dry and heal with less chance of airborne fungi getting into them. Try not to touch the cuts after they have been made.  Use clippers for a clean cut. Wash your tools and hands often.Trimming away infected leaves is a sad and tedious process. It’s practically impossible not to spread the fungi as your touch leaves that have it and try to remove them without touching any other stems or leaves. The very cuts you make are open to fungi. Then, naked stems are susceptible to sunscald – see image below. You come back a few days later and more leaves are wilting. The disease is internal, has spread out to the leaves. At some point soon after that, a lot of gardeners pull the suffering plant. It’s done. Not good to leave it and let windborne fungi infect neighboring plants.

    Do not compost infected plants or trimmings. The fungi has amazing survival ability and being soil borne, it is right at home in your compost. Put it in the trash, carefully bagged so as not to spread or leave any trace. Wash your hands. If you can, burn the infected plants.

  • The wilts can’t be stopped. Sooner or later the plant leaves curl lengthwise, get the dark spots, turn brown then blacken and hang sadly. Plants can produce but the fruit doesn’t ripen properly if it does produce. It’s agonizing to watch. Sometimes they somewhat recover later in the season after looking totally dead. You had stopped watering them, summer heat dries the soil and kills enough of the fungi for the plant to be able to try again. But production is so little and fruits don’t ripen properly. It’s better to pull it, reduce the fungi population that can blow to other plants. The safest bet is to remove the entire plant. Get all of the root as best you can. The root is where the wilt’s mycelium first congregate and infected roots left in the ground will start the whole process again. Replant in a different place if possible.

Tomatoes pruned to remove diseased leaves of Fusarium and Verticilllium wilts are susceptible to sunscald.Preventive Foliar Mix that can help! 

Apply to newly installed transplants, and during the season every 2 to 3 weeks, so new growth will be covered. Wet both the undersides and tops of leaves. Per gallon add:

  • One dissolved regular strength aspirin
  • 1/4 Cup nonfat powdered milk
  • Heaping tablespoon baking soda
  • 1/2 Teaspoon mild liquid dish soap

After the tomatoes set, add some nitrogen. Boost your plant’s immune system with some worm castings at the same time. You don’t want to add too much nitrogen to your tomatoes before they set fruit. Too much nitrogen before fruiting leads to more leaves and less fruit. Add N only once. Stressed plants are the most susceptible to the fungus. Water regularly and deeply. Use well-balanced, slow-release organic fertilizers that aren’t overly heavy with nitrogen. A healthy plant tends to fight off the spores.

Blight can also be transmitted through seed, so NO seed saving from infected plants. Fresh seeds and resistant varieties are in order.

Remove volunteer tomatoes and potatoes. If they are a not a resistant or tolerant variety, when they get sick, they increase the chances of your resistant varieties having to fight harder to live, and your good dear plants may not win the battle.

Air circulation, plant staking and no touching. Air circulation allows the wind to blow through your plants. This allows the timely drying of leaves and it helps break up micro climates. If your plants are packed too tightly together, they themselves become barriers to drying. Staking your plants to poles and using cages helps them grow upright and it creates gaps between the tomato plants. You want wind and sun to reach through and around your plants. Moisture is needed for fungi to spread. Dry is good. Tomatoes should be planted with enough distance that only minor pruning is needed to keep them from touching each other.

Spray proactively. Wettable sulfur works. It is acceptable as an organic pesticide/fungicide, is a broad spectrum poison, follow the precautions. It creates an environment on the leaves the spores don’t like. The key to spraying with wettable sulfur is to do it weekly BEFORE signs of the disease shows. Other products also help stop the spread. Whatever you select, the key is to spray early and regularly.

At the end of the season remove all infected debris, don’t compost. Don’t leave dead tomato, eggplant or peppers in the garden to spend the winter. Pull weeds because spores can over-winter on weed hosts. Many weeds, including dandelions and lambsquarters, are known to host verticillium wilt. During our winter season, turn your soil about 10 inches deep. Let the soil dry and the fungi die. Burying the spores helps remove them, it disturbs cucumber beetle eggs and exposes snail eggs to die!

If you have space, crop rotation is an important tool in fighting wilt. If you’ve had trouble with wilt, don’t plant potatoes, eggplant, or other solanaceous vegetables where any of them have grown for at least four years.

Practice prevention, be vigilant. If you don’t have wilts in your soil you are so blessed! 

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The Green Bean Connection started as correspondence for the Santa Barbara CA USA Pilgrim Terrace Community Garden. All three of Santa Barbara city’s community gardens are very coastal. During late spring/summer we are often in a fog belt/marine layer most years, locally referred to as the May grays, June glooms and August fogusts. Keep that in mind compared to the microclimate niche where your veggie garden is. Bless you for being such a wonderful Earth Steward!

Love your Mother! Plant bird & bee food! Think grey water! Grow organic!

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Healthy care and choices make the difference!

Give your plants a chance!

Not too much N (Nitrogen)  It imbalances your plants, just like too much sugar for us.  You get lots of leaf, no fruit, growth is too fast and ‘soft,’ inviting to pests and diseases.

Watering practices make a difference.  Overhead watering is not good for most plants, but especially not for fuzzy plants that like it dry – tomatoes, eggplant.  Too much nighttime wet equals mildews and more slugs and snails, more remedies and pest prevention, more costly.  Plants drink during the day – water in the AM when you can.  Make furrows, water deep, let it soak in laterally.  Make basins to keep water where you want it.  Drip systems usually don’t work in a veggie garden you are planting biodiversely, mixing things up.  Also, veggies come and go pretty quickly in an active garden.  If you are row or patch planting, if the area is long or big enough, a drip system could work well. 

  • Water soaked soil is dead soil.  Soil organisms, soil builders, simply drown.  If in a low spot, check your drainage options; build a raised bed.  Add organic water holding compost, water less no matter how much fun it is!
  • Dry soil is dead soil.  Nitrogen off gases, your soil organisms die or go away.  See if you can channel some water to that area.  Install furrows or build soil walls or basins to keep water where it is needed, avoid wasteful runoff.  Again, add organic water holding compost.  Water deeply.  If you are gardening at home, busy and forgetful, perhaps you could install drip irrigation on a timer. 

Avoid spreading viruses that can spread diseases.  Really check those plants you buy at the discount nursery.  Remove diseased plants and don’t compost diseased plants.  This is a tough decision when it comes to disease tolerant plant varieties.  They can have a disease yet still produce.  They are bred to do that.  Is that ethical?  If you are gardening at home and make that choice, that is one thing.  If you are in a community garden, and the disease is windborne, is it fair to your garden neighbors?  Maybe we all need to get tolerant varieties.  

Some diseases lurk in garden border weeds.  Or you can bring them into the garden by walking through weeds.  Insects bring some diseases and so do animals, like our skunks, raccoons, possums.  If the ‘weeds’ are habitat for beneficial insects, be careful what you remove, consider the balances. 

Ants.  Whether you mind them or not probably depends on how many there are and what they are doing.  If they are tending aphids, no!  Not only are there ants with aphids, but white flies are attracted to the aphid honeydew as well.  Otherwise, ants are virtuous hard working cleaner uppers!  The take away dead insects.  Balance is the key. 

Varieties matter.  Planting a variety out of season makes that plant struggle and be vulnerable to pests and diseases it can’t handle.  In Santa Barbara we have the cool damp ocean areas and the hot dry foothills.  Different varieties will thrive in one and not the other.  Planting too early or too late, your plant will try, but may not be able.  Some gardeners are totally pro Heirloom, against hybrids.  But Nature herself hybridizes, it is a natural process.  It occurs naturally by area and plants that grow there do the best there.  In a way, we subtly do a similar thing ourselves when we select seed from our best plants.  I think being flexible in your choices will get the best all around results. 

Planting at the Right Time makes a big difference.  Sometimes you just won’t get germination if it is too cold or hot.  Or a plant thrives in temporary weather, but dies when it goes cold again, or too, too hot.  They need certain temps and day length.  Some may survive, but never thrive later.  That is sad to see.  So respect them.  Know them well enough to honor their needs.  Planted at the wrong time, pests they aren’t equipped to handle may eat them alive.  If you are a big risk taker and financially don’t mind a few losses, go ahead.  Some will succeed, for sure.  You may or may not get earlier production.  Sometimes plants can be planted a month apart, but the later one will ‘catch up,’ and produce at the same time as the earlier plant!  Same can be true of smaller and larger transplants because it all depends on temps and day length.

Once your plants are going, sidedressing keeps them going!  Sidedressing usually starts when your plants start to bloom, make fruits.  Scatter and lightly dig in a little chicken manure and/or lay on a ½” of tasty compost, some worm castings, water on some fish emulsion, blood meal if they are yellowing and could use a quick Nitrogen boost.  Water well.

Plant appropriate varieties on time, water and amend well, keep watch on pests and diseases.  Robust happily producing plants are worth it, and a joy to watch!

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APRIL is for Heat Lovers! Pull back your mulches, let soil heat up, PLANT!

Why not start with an AAS (All America Selections) 2011 Winner?!
Pepper ‘Orange Blaze’ F1  Early ripening orange variety, very sweet flavor, multiple disease resistances!

AAS 2011 Winner - Orange Blaze F1 Pepper

Get out last year’s garden notes if you made any, and review for varieties you liked, where you got ‘em, how much to plant!

CORN!
Plant in blocks, not rows, for pollination.  When tassels bloom, break off pieces and whap them on the silks!  Each silk is one kernel, each needs one grain of pollen!
Corn hybridizes – plant only one variety, or varieties that don’t have pollen at the same time.  This is pretty much not doable at a community garden since everyone is planting all kinds at any time, so if you harvest seeds, don’t expect true results!

Heat tolerant, tipburn resistant lettuces – Nevada, Sierra, Black Seeded Simpson, Jericho Romaine
     Slo bolt cilantro, arugula in semi shade (among your corn?!)
Eggplant love humidity and heat.  Tuck ‘em in between, right up against, other plants.  Near the cooler coast plant the longer length varieties that mature earlier.
Jicama, limas, melons, okra, peppers, seed potatoes, pumpkins
From Seed:  basil (Nufar is wilt resistant), chard, green beans (while peas finishing), beets, carrots, corn, endive, New Zealand spinach, parsley, radish, squash – summer & WINTER, sunflowers, turnips.  Coastal gardeners, get your winter squash in NOW so it will have ample time to mature.
The radish variety French Breakfast holds up and grows better than most early types in summer heat if water is supplied regularly.

PreSoak and/or PreSprout for 100% success!  Click here for details!  Per eHow:  How to Soak Watermelon Seeds in Milk Before Growing.  Sometimes the seed coat carries a virus, and the proteins in milk will also help deactivate the virus.  Read more 

Transplants:  cucumbers (hand pollinate?), tomatoes, watermelon
WAIT FOR MAY to plant cantaloupe
Herbs from transplants – oregano, rosemary, sage, savory, thyme 

Plant successively!  If you put in transplants now, also put in seeds for an automatic 6 week succession!  Plant different varieties (except of corn if you want true seed – see above)! 

If you overplant, thin for greens, or transplant when they are about 2 to 3 inches high.  Lettuce, carrots, onions.  Too many stunt each other.  OR, this from Santa Barbara Westsiders Lili & Gabor:  Overplant mesclun on purpose, then mow the little guys!  If you are at home, plant densely in a planter bowl, cut off, leaving 1 ½” of stem still in your soil.  They will regrow, you will have several months’ supply of tasty baby greens.  Plant two or three bowls for more people or more frequent harvest!  Give a bowl as a gift! 

Tomatoes
Plant for excellence
 – Throw a handful of bone meal in your planting hole along with a handful of nonfat powdered milk, worm castings, compost/manures, mix it all up with your soil.  Sprinkle the roots of your transplant with mycorrhizal fungi!  That’ll do it!  Stand back for bounty!
REMOVE LOWER LEAVES OF TOMATOES  Wilt prevention.  Water sparingly or not at all after about a foot tall.  Wilt comes from the ground up the leaves and is airborne. Remove any leaves that touch the ground or could get water splashed.  Don’t remove suckers – airborne fungi can enter open wounds.
Sorry, NO HEIRLOOMS if you know the soil has the wilts.  Heirlooms don’t have resistance.  Get varieties with VF on the tag or that you know have resistance/tolerance.
Mid day, rap tomato cages or the main stem, to help pollination.  55 degrees or lower, higher than 75 at night, or 105 in daytime = bud drop.  Not your fault.  Grow early varieties first that tolerate cooler temps.
Pilgrim Terrace Community Garden Kevin and Mary Smith have had successes with 2 blight resistant/tolerant determinate varieties, New Hampshire Surecrop, a 78 day, great tasting slicer/canner, and Legend, a very early 68 day!  Ask for them, and more Jetsetters, with unbelievable VFFNTA resistance/tolerance, at your nursery.  See Tomatoes and Wilts here at the Green Bean Connection Blog for a list of additional resistant/tolerant varieties and tips!   

Maintenance!  Sidedress when blooms start.  Fish/kelp, foliar feed Epsom salt for Solanaceaes, seabird guano (not bat) for more blooms, manures for lettuces and leaf crops like chard, collards.

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Powdery Mildew on Peas

Select powdery mildew resistant or tolerant varieties!

Cornell University’s lists of Disease Resistant Varieties

  • Longbeans
  • Green beans:  Provider, Merpatim, Parkit, Perkutut, Sriti
  • Cucumber: Diva, Cumlaude, Media F1.  Slicers:  Cornell’s list
  • Muskmelon:  Ambrosia F1, Primo (western type), Sun Jewel
  • Pea:
    • Ambassador – Resistant to powdery mildew, entation virus and fusarium wilt
    • Cavalier – Good resistance to powdery mildew.
    • Greenshaft – Resistant to downy mildew and fusarium wilt
    • Rondo – Resistant to fusarium wilt
    • Downy Mildew resistant peas:  Kelevdon Wonder, Oasis, Twinkle, Avola, Hurst Greenshaft, Ambassador, Cavalier and Peawee.
  • Pumpkin: 18 Karat Gold, Gladiator
  • Winter Squash:  almost all varieties
  • Yellow Summer Squash: Success, Sunray, Sunglo
  • Zucchini: Ambassador, Wildcat, Cornell’s list

Healthy Practices Make a Difference!

Plant in full sun!
Plant so leaves of one plant don’t touch another and spread the spores.
Remove any debris or dead leaves breeding habitat.
Remove and don’t compost infected leaves.  If  you don’t remove them, you reinfect your plant each time you water. 
Wash tools and your hands before you go from one plant to the next.
Water in the AM, at ground level.  No overhead watering.
BEFORE you have mildew, while your plants are still babies, drench the leaves with a baking soda/milk mix.  Tablespoon Soda, ¼ cup nonfat milk powder, drop of liquid dish detergent in a watering can.
Drench weekly with your mix.  But if you think you aren’t going to be able to get rid of the mildew, sadly, do the one cut prune.  Remove that plant so it won’t infect others – yours or your neighbors’.  Do this sooner than later.  Mildew is windborne, so the more mildew, the more is spread.

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