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Archive for August, 2016

Common dodder covers some host plants

On a walk in the Smoky Mountains last summer, we came across a patch of plants that were covered with what looked like yellow Silly String. It was crazy looking! Strands and strands of fine golden strings were draped over and twining around these poor plants.

Common dodder (Cuscuta gronovii) covers some host plants

Common dodder (Cuscuta gronovii)
covers some host plants

Eric knew what it was right away – dodder; a parasitic vining plant also known as scaldweed, strangleweed, devil’s hair, devil’s guts, love vine, and many other equally descriptive common names.

Dodder (Cuscuta spp.) is an annual plant that is effectively leafless and has contact with the soil only as a young seedling. These plants do not manufacture chlorophyll so they are unable to produce their own food through photosynthesis like green plants can. With the exception of the first few days after germination, dodder is entirely dependent on a host plant for the water and nutrients needed to complete its life cycle – an obligate parasite!

Flowers of common dodder

Flower clusters of common dodder

Despite its lack of chlorophyll, dodder IS a flowering plant and produces many clusters of tiny flowers from June through the fall. If pollinated, the flowers will form seeds just like other like flowering plants. In fact over the course of a season, a single dodder plant is capable of producing thousands of seeds!

Dodder seeds typically germinate in the spring and the seedlings, which have thin, vine-like stems, grow upwards and twine around the first solid object they encounter. Since the dodder seeds generally drop to the ground under the mother plant, the seedlings normally germinate among suitable host plants. For the first few days of growth, the dodder seedlings survive on nutrients stored in the seed. If they do not contact a host plant within 5-10 days, they will run out of food and die.

Dodder stem produces haustoria which penetrate the host stem

Dodder stems produce haustoria
which penetrate the host stem

Once dodder contacts a host plant, it quickly twines around the stem of the plant and small structures called haustoria are produced along the dodder stem. The haustoria penetrate the vascular system of the host and begin to extract carbohydrates and water from its stem. At this point, the dodder plant is completely supported nutritionally by the host. The original (seedling) stem of the dodder eventually withers and this parasitic plant loses contact with the soil.

Once attached to a host plant, dodder continues to grow and reattach in multiple places along the host stem. Individual plants will often spread to nearby host plants creating a mass of stringy orange stems which can cover large areas. This is what we came across on our hike in the Smokies.

A tangle of dodder stems intertwine to form a stringy mat.

Many dodder plants intertwine to
form a tangle of stringy stems.

Parasitic organisms rarely kill their hosts since they rely on them for sustenance. Dodder is no exception and, though they may weaken and stunt the growth of the host plants, they generally do not kill established plants. However, if they attach to seedling plants, they can seriously weaken them and may end up killing these young plants.

If it becomes established in agricultural fields, dodder can cause a significant reduction in crop yield. Alfalfa and sugarbeets are common host plants for some species of this parasitic plant. It can also infest ornamental plants including many perennials and annuals. Japanese dodder (Cuscuta japonica) often parasitizes trees and shrubs, including many types of fruit trees.

Seed capsules of common dodder contain up to 4 seeds each.

Seed capsules of common dodder
contain up to 4 seeds each.

This is one unusual plant!

It can become a serious garden pest and unfortunately it is usually difficult to control. If you pull the stems off the host plant, any haustoria that remain embedded in the host stem will resprout and continue to parasitize the plant. If it is allowed to set seed, thousands of seeds can drop to the ground!

A pre-emergence herbicide can prevent the germination of dodder seeds but these seeds have a hard seed coat and have been found to remain viable in the ground for more that 20 years! Yikes!

One recommendation for control of dodder in the garden is to completely remove all the host plants and replace them with a non-host species. Thus any dodder seedlings that germinate will not find a suitable host and will die off.

If you find this crazy parasite in your gardens, I hope you are able to win the battle against it!

Until next time – Happy Gardening!

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These days everyone is concerned about proper nutrition and what we put into our bodies; but what about our turfgrass and the plants we grow? How do we take care of their nutritional needs?

Good rich soil provides the perfect growing environment for your plants

Good rich soil provides the perfect
growing environment for plants

Soil is obviously very important to plant growth. It not only provides a physical medium in which your plants grow, it is also a reservoir of nutrients, air, and water – three requirements for plant growth.

Most of the nutrients needed for the growth and development of plants are absorbed from the soil by the roots. Over the seasons, these soil nutrients become depleted and must be replenished or plant health will decline.

Because the makeup of the soil is so important to the health and well-being of your plants, it should become very important to you as a gardener.

Awareness of the properties of your garden soil will allow you to adapt your cultural practices so your soil environment will be most conducive to healthy plant growth, whether it be a flower garden, vegetable garden, or your lawn. The nutrients that will give you a thick, lush, and green lawn are very different than the nutrients required to have a thriving and productive vegetable garden.

Understanding Plant Nutrients

There are 17 chemical elements known to be essential for plant growth, flowering, and fruiting.

Primary macronutrients

Maintaining a lush green lawn requires more nitrogen and correct pH.

Maintaining a lush green lawn
requires more nitrogen
and correct pH

The primary macronutrients, nitrogen (N), phosphorus (P), and potassium (K), are used in the largest amounts by plants and are thus prone to deficiency in soils. These nutrients are the primary ingredients in most garden fertilizers and the percentages of each are prominently displayed on the bag as the N-P-K numbers. These percentages are always presented in the same order – nitrogen, phosphorus, potassium.

Nitrogen is required for healthy vegetative growth (leaves and stems) and is especially important in young plants. High levels promote dark green leafy growth but not fruits and flowers. Thus a fertilizer higher in nitrogen is great for lawns and leafy vegetables but disastrous when you are trying to grow tomatoes!

Phosphorus is important in all functions of plant growth but especially for root development and growth, and in the production of flowers, fruits, and seeds. Starter fertilizers, which can be used when transplanting trees, shrubs, and perennials, are much higher in phosphorus than nitrogen and potassium. They stimulate root growth and help avoid transplant shock. “Bloom booster” fertilizers with 20%-30% phosphorus help promote flower bud formation.

Potassium is important for the overall vigor of plants. It promotes disease resistance, root formation, and cold hardiness. Plants deficient in potassium will have weak roots and stems.

Secondary macronutrients

The secondary macronutrients are calcium (Ca), magnesium (Mg), and sulfur (S). These nutrients are very important to plants but are used in smaller amounts than the three primary macronutrients.

Micronutrients

Micronutrients, also known as trace elements, are not nutrients of lesser importance to plant health but those that are required in minute quantities. With the exception of iron and manganese, micronutrients are seldom deficient in our garden soil, however, some can become unavailable to plants when the soil pH is either too high (alkaline) or too low (acidic). Maintaining your soil pH between 6.0-6.5 will keep these nutrients available to the plants. Some fertilizers are fortified with micronutrients.

What’s in YOUR soil?

A bountiful harvest depends on building and maintaining proper soil nutrients.

A bountiful harvest depends on
providing proper soil nutrients.

So your lawn is thin and patchy or your vegetable garden is not producing like it used to or your plants just aren’t blooming? It may well be your soil. You probably need to add fertilizer, but what kind and how much? Is your soil deficient in nitrogen? Maybe phosphorus? Perhaps the pH is not optimal. How would you know?

The easiest way is to get your soil tested. Sound hard? Not really and the analysis from these tests will allow you to make informed decisions on how to improve the soil environment for your lawn and garden plants. If you choose to have your soil tested professionally, you will not only be provided with a detailed analysis of the soil but you’ll also receive specific recommendations for amendments to improve the pH and also nutrient content if necessary.

Easy Online Soil Testing …

ThinkSoilThe lawn care professionals at MyTurfandGarden.com have developed a unique, on-line and very straightforward way to test your soil. It’s called Think Soil™.

A soil analysis from Think-Soil™ will provide essential information on relative levels of organic matter, pH, lime requirement, cation exchange capacity (CEC), and levels of plant-available nutrients contained in your soil.

Simply go to MyTurfandGarden.com, and click on Soil Testing in the top menu. There you can read all about it and see how easy it is.

Follow the instructions or watch the YouTube video demonstrating how to take a soil sample from your garden or lawn. Within days of placing your order, you’ll receive a pre-addressed envelope, a leak proof zip-lock baggie, and detailed instructions. After you collect your soil sample, just place the baggie with the sample into the pre-paid envelope and give it to your postal carrier. There is no cost for shipping.

Once your soil sample arrives at the lab, the test results will be ready for you to review within 36 hours. You will be notified by e-mail as soon as the test results are available.

Beautiful lawns and gardens require proper nutrition and soil properties

Beautiful lawns and gardens require
good soil with proper nutrients
and amendments

In addition, Think-Soil™ consultants are available toll free to help with any questions about your test results and to offer advice on what’s needed to remediate your soil. For the first time you’ll have the information needed regarding how much product is needed, how best to apply it, and when to do it.

For the month of August, Think-Soil™ has an introductory offer of 50% off all soil tests plus no cost to send your soil sample.

Doing a soil test is one of the best ways to insure that you amend your soil to provide just what your lawn, vegetables, and/or your flowers need to thrive.

Remember next month is Lawn Care Month. September marks the beginning of the best season for most lawn projects. Be ready!

“Don’t Guess – Do the Test!”

Until Next Time – Happy Gardening!

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Sad looking tomato plants

I'm pretty sure these Rutgers tomatoes are supposed to be bigger than 2" in diameter!

I’m pretty sure these Rutgers
tomatoes are supposed to be
larger than 2″ in diameter!

My tomatoes are a disaster this year!

Their growth is slow and they are not producing many flowers or fruit. Plus, the fruit that has formed is way smaller than it should be. It’s very disappointing!

I planted about 40 plants which included 9 different varieties, most of which are heirlooms because they are so delicious. Normally by this time of the season, the plants would be lush and full and looming over the top of our 6 foot trellises. There would also be lots of beautiful full-sized tomatoes with many more coming on. Not so this year!

The season started out on a downside when, within a few days of planting out my transplants, we noticed some severe cupping and curling of the foliage especially on the youngest leaves. When I saw it I immediately thought – classic 2,4-D herbicide injury! I wish I had taken some pictures of the damage.

Tomato injury caused by 2,4-D

Tomato injury caused by 2,4-D

It affected all of the tomato plants. I also noticed 2,4-D injury on our grape vines which are growing on the hill above the vegetable garden. Tomatoes and grapes are especially sensitive to broadleaf herbicides. Even light exposures can result in injury to the plants. If an herbicide like glyphosate (Roundup) or one that contains 2,4-D or dicamba is applied in the vicinity of a vegetable garden, it can easily drift onto the plants. Herbicides can drift pretty far if caught by the wind! We hadn’t sprayed anything but we found out later that a neighbor had been spraying a product containing 2,4-D to control thistle in the field right beside our vegetable garden. The spray must have drifted onto our newly planted tomatoes.

Strike One!

 

The spindly vines have a lot of diseased foliage.

The spindly vines have a lot
of diseased foliage.

We planted our tomatoes and most of the rest of the garden on the 21st of May. June had higher than normal rainfall, often in the form of heavy thunderstorms. This wet weather led to disease problems, especially in our heirloom varieties which make up about 80 percent of what we grow. We always have some disease in our tomatoes that wipes out their lower branches but it never seems to affect their production much. This year it was much worse. I am pretty convinced that the herbicide injury weakened and stressed the plants and left them more susceptible to fungal diseases.

Strike Two!

 

Hornworm damage on the Better Boy tomatoes

Hornworm damage on these
small ‘Better Boy’ tomatoes

Though we never seem to have much insect damage on our tomatoes, we have had an occasional hornworm on the plants. So far this year, Eric has discovered two hornworms on the tomatoes but only after they had almost completely defoliated a couple of the plants and chewed a few of the tomatoes as well! They are well camouflaged and it took a bit of hunting before he found and squashed the two culprits. Hopefully there aren’t more lurking among the foliage.

Strike Three!

 

With all these strikes against them, the plants have suffered tremendously. The foliage is sparse and the stems are elongated and spindly. I think this is mainly due to the herbicide injury early in the season.

The 'Pruden's Purple' tomato on the right is deformed and cat faced but at least it is larger.

The ‘Pruden’s Purple’ tomatoes
are small and some are deformed.

Though the plants have slowly outgrown the damage and the new growth is fairly normal, the plants are stunted and few flowers are being formed. The fruit that has formed is mostly remaining very small. I harvested a few medium-sized ‘Cherokee Purple’ tomatoes but most were deformed with severe cat facing (another symptom of 2,4-D injury).

Some of the problem may be environmental, too. I have heard that other people are having similar issues with their tomatoes; slow growth and the production of very few tomatoes that are all small in size. It may just be a bad year for growing tomatoes!

Unfortunately, it doesn’t look like we will be harvesting very many tomatoes this year. We should have enough to enjoy fresh but I’m pretty sure we won’t get enough to can.

The pole beans are doing very well!

The pole beans are doing very well!

On the bright side, the pole beans are doing very well except for 2 or 3 poles where some critter has nipped off the lower leaves. The vines are still strong and producing lots of beans at the top. We planted Rattlesnake beans, a purple pole bean, and a new one for us – Lazy Housewife Pole Beans. Yum!

The cucumbers have also produced well this year. So far I’ve made 23 pints of my famous bread and butter pickles and still have plenty to slice up for my lunches and I’ve even given a bunch away! I’ll be making more pickles this weekend and freezing beans, too!

I’m just so sad about my tomatoes …

Until next time –
Here’s hoping your tomatoes are doing better than mine!

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