Centipedes, Millipedes and Squash Vine Borers

Adult Squash Vine Borer, Photo by Jeff Hahn

Adult Squash Vine Borer, Photo by Jeff Hahn

We got a question today from a customer who says centipedes are damaging the roots of his squash plants. "I noticed a bunch (maybe 50) centipedes on the roots of my squash plants."

First of all, they are probably millipedes. Centipedes (which have one set of legs per segment) would be eating other insects. Millipedes (two sets of legs per segment) are sometimes found in large numbers in moist garden soil that contains a lot of organic matter because they feed mainly on decomposing organic matter. Sometimes they will damage young seedlings, but usually the problem starts otherwise; and the millipedes are eating the damaged, rotting stems and roots. For instance, if your soil is staying too wet or if you’re watering late in the day, the problem may have started with root rot. Or if you have squash vine borers, the millipedes will feed on the damaged stems. If you do think your problem is starting and ending with millipedes, I’d apply some diatomaceous earth (or Organic One which is diatomaceous earth with pyrethrin) around the base of the plant and wherever it touches the soil. Do not use more than you have to however, as this will affect your earthworms also.

In any case, count on squash vine borers to cause problems with this crop. I recommend drenching the stems of your squash plants (especially at the base) with Thuricide (liquid Bt) at least a couple times per week and more if you have time. The moths will lay eggs at the base of your plants, but they will be protected when the larva hatches if it has to eat its way through Bt to get into the stem (the borers/larva will be dead before they can do any real damage). Keep an eye out for the moths which are active during the day. As you can see from the photo, they’re pretty distinctive. Kill them whenever you can, and increase the Bt treatments while they’re active.

 One more caution about watering. You’ll avoid a lot of problems simply by watering early and giving the plants time to dry before evening, but be aware that overhead irrigation will wash the Bt off the squash stems. Drip irrigation solves this problem and (since it does not get the foliage wet) relieves the necessity to water early. If this is not an option, you may want to increase the number of Bt treatments to replace product that has been washed off.

Frankly if I did not love yellow crookneck squash and zucchini as much as I do (and if homegrown squash did not taste so much better than what you get at the store), I would not go to this much trouble. But I do (and it does), so it’s definitely worth the extra work.

Get a handle on homegrown tomatoes in containers!

If any vegetable is worth growing at home, it is the tomato. Most store-bought varieties are selected for traits like durability, productivity, disease-resistance, uniformity, and roundness, but not necessarily taste. Even the most expensive grocery store ‘mater can’t compare in flavor to a truly well-ripened homegrown tomato.

Tomatoes are therefore an ideal ‘gateway’ vegetable for folks interested in vegetable gardening, and growing in containers is a great way to start. Digging in the ground can seem intimidating and pots require little planning: whether on your lawn, deck, or driveway, you’ll only need a spot with at least half a day of direct sunlight.

Want to learn more about growing tomatoes in Tallahassee? Join me at Native Nurseries for the Totally Tomatoes workshop at 10 a.m. Saturday.

If you’ve tried growing container tomatoes before and failed, it was probably due to your choice of container. At least a seven-gallon size container is required for each tomato plant, although for dwarf or bush varieties you could successfully use a five-gallon pot. It’s tempting to skimp on the size, but beware. If you plant in a smaller container, you will be watering several times a day once July rolls around, and you will still likely have serious consequences.

Tomatoes need a lot of water to sustain all of their growth in the heat of the Florida sun. They can dry out rapidly, and while they may bounce back, the fruit will split or suffer from blossom-end rot, making it inedible. Drying out also stresses the entire health of the plant, weakening its immune system, and making it more susceptible to pests and disease. Many of the “problems” people experience with growing tomatoes are actually secondary symptoms of insufficient watering. For this reason, I prefer using plastic containers rather than terra cotta, because they retain more moisture, and they’re lighter and easier to move. I’ve also had really great success with large, reusable grow-bags.

The container you choose must have adequate drainage. I have too often seen big box stores selling planters that have tiny, inadequate drain holes – or even none at all! This is a setup for certain failure. Plants in soil with poor drainage will result in bacterial growth that quickly rots your plants.

For soil, I like to use a mixture of about one-fourth mushroom compost and three-fourths potting soil. I also add a cup of Espoma’s Tomato-tone fertilizer, a handful of worm castings, and a tablespoon of Epsom salts.

It is especially important to plant your young transplant deeply in your pot. Pinch off the lower leaves along the stem, and plant the tomato as deeply in the soil as the size of your transplant allows; making sure to keep at least three inches of the growing tip above the soil.

Wild tomatoes native to South America are rambling, perennial vines with small, usually yellow, fruit. The vines grow on the ground, and are able to put out roots all along their stems to sustain the large vines with adequate water and nutrients. When we trellis or stake tomato plants, they are unable to root from their stem, which makes it difficult for them to source all of the water and nutrients they need to support their vigorous growth. This is why planting tomatoes deeply is key.

You will need a strong and sturdy tomato cage, or a stake of at least one-inch diameter and six feet tall to support most tomato plants. I use thick, six-foot cypress or bamboo stakes and then use twine to loosely wrangle the stem. Most tomatoes grow at least six feet tall with multiple stems, so you’ll have to keep up with the twine as it continues to grow.

Choosing the right variety of tomato is also important. I always recommend cherry-sized or small slicing tomatoes for pots. They are just generally more productive and easier to grow than the big beefsteak types, which can be finicky. They’re also more tolerant of shade.

A few of my favorite varieties for pots are Sungold cherry, Juliet, Jaune Flamme, Dark Galaxy, and Nyagous. These varieties are all early ripening, productive, and most importantly, delicious!

Safe Solutions - Natural Herbicides

Safe Choices for Weed Control

For homeowners looking for products that will help them in their constant battle with weeds, products that will not harm them, their children, their pets or the planet, the news is good. In recent years, there have been some great new products; and now for the first time, we even have a safe, selective herbicide to offer. Finally you can kill weeds in your lawn without harming the grass and without using 2,4-D. It’s called Weed Beater Fe (active ingredient is iron HEDTA - soluble iron); and from what I’ve read so far, it seems to be somewhat effective on some weeds and very effective on others (oxalis for one). Here in Florida we can even use Weed Beater Fe in the winter, as long as you have weeds actively growing. However, do not apply this product on days when the daytime temperature will exceed 85°. If your lawn needs water, irrigate it first and then apply the product after the grass has dried. Weed Beater Fe is available in a ready-to-use formulation only (quarts and gallons).

Maize Weed Preventer is an effective, natural pre-emergent herbicide (suppresses weed seed germination). It is a ready-to-spray liquid formulation (one quart bottle—attach it to your hose) of corn gluten. Because it does not have nearly as much nitrogen as the granulated form, it can be used earlier in the season and more often. According to the manufacturer, you can use Maize up to four times per year. Wait at least a month between applications.  It is best to apply this product in the spring and fall when temperatures do not exceed 90°. If you must apply Maize Weed Preventer during the heat of the summer, water your lawn in the morning and then apply Maize in the evening after the temperature drops below 90°. As with Weed Beater Fe, you should always avoid using this product when your lawn needs irrigation—irrigate first, then apply after the grass dries. Definitely do not apply Maize in newly seeded areas as it will suppress all seed germination (not just weed seeds).

We have two safe products for when you are in need of a contact herbicide. These products are usually used around driveways and sidewalks and around the base of mature trees, buildings and fence lines. Care must be taken if you use them on weeds in close proximity to plants you do not want to harm. They will kill or damage any plant you apply them to. Bonide BurnOut is rainproof when dry, works at temperatures as low as 40° and does not translocate. Made from natural ingredients (citric acid and clove oil), BurnOut is approved for organic gardening and is safe for use around people and pets. It’s available in concentrate and ready-to-use formulations (one quart bottles). Monterey Herbicidal Soap (active ingredient - Ammoniated Soap of Fatty Acids) is an environmentally-friendly product that quickly controls and kills moss, weeds and algae and also does not translocate. It is fast acting, providing results within hours after application. It may be used whenever desired but is most effective during warmer weather. It does not stain bricks, concrete or asphalt. We originally began stocking Monterey Herbicidal Soap at the request of a customer who uses it to control poison ivy but got tired of paying the freight charges that came with online ordering. We’ve since had good feedback from other customers trying this herbicide for the first time. It comes in a one gallon concentrate.

So if (when) you have problems controlling weeds in your landscape and you get tired of pulling, come see us and we can help you choose the right (safe) product for your situation.