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FAQs - Vegetables

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FAQs - Late Blight on Tomatoes

We are planning a vegetable garden and the only spot we have for it is in partial shade. Can you tell us what vegetables we can plant, if any, in a shady area? What is the worst that would happen if we plant sun loving vegetables in that area?

For the past few years, my tomatoes, cucumbers and squash flower but produce little fruit.  My plants grow large and look very healthy, but production is very disappointing.  What am I doing wrong?

Recently I noticed the yellow blossoms are dropping off my tomato plants.  Is there something lacking in the soil that is causing this?

Thinking ahead, I would like to get a jumpstart this fall on a vegetable garden for next season. What is the best way to go about this?  I am interested in making a raised bed

It is September and my tomatoes still have fruit on them.  I am afraid they will not get the chance to ripen on the vine before the frost. What can I do with all these green tomatoes?

This summer I grew a nice collection of herbs in containers that I have enjoyed using when I cook. The thyme, mint, sage and rosemary are still producing and look beautiful. What can I do to protect them this winter? Is it okay to bring them inside?

I am a beginner vegetable gardener and have a pretty basic question. What is the best way to water a vegetable garden and how much water should I give my plants?

My four raised vegetable beds are overgrown with weeds that I did not clear out in the fall. Is there something I can do now to control the weeds or should I just wait until spring to pull them out?

This has been another disappointing year for my lima beans.  For the past 2 years, I have planted Dr. Martin lima beans with little success.  The vines looked very healthy and blossomed all summer, but did not produce pods or if the formed they quickly dropped from the vine.  Can you shed some light on what is going on?  I have been growing limas for years now.

My tomato plants were very healthy this season. I am now noticing some of the leaves turning yellow and then browning. Is this something I should be concerned about? The plants are still producing and I want to make sure I can harvest the rest of the tomatoes.

Is it safe to use cement blocks to build a raised garden to grow vegetables? I heard about unsafe chemicals in these cement blocks that could leech into the soil and plants.

We are planning a vegetable garden and the only spot we have for it is in partial shade. Can you tell us what vegetables we can plant, if any, in a shady area? What is the worst that would happen if we plant sun loving vegetables in that area?

Ideally, your garden should be on level ground in a spot that gets at least 6 hours of full sun a day or more. Is it possible to prune the trees and shrubs in the area to let more light in? If not, you will need to forgo planting sun loving vegetables like tomatoes, eggplants, squash and peppers. In too much shade, they will produce a poor crop. In general, leafy vegetables such as lettuce, arugula and spinach can tolerate the most shade. Carrots, beets, Swiss chard, kale, and mustard greens will produce if they receive about 5-6 hours of sunlight.  Another alternative is gardening in containers. Their portability allows you to move them to the sunniest area of your yard.

For the past few years, my tomatoes, cucumbers and squash flower but produce little fruit.  My plants grow large and look very healthy, but production is very disappointing.  What am I doing wrong?

Poor fruit set in vegetable crops can be caused by prolonged dry or wet soil conditions, very high (can kill pollen) or very low temperatures, excessive shade, overuse of nitrogen fertilizer, and hot, dry winds. Excessive nitrogen may be the cause of your problem, because you mention that the plants grow large. Using insecticides in the garden that kill pollinating insects also causes poor fruit set. Do not apply insecticides (other than insecticidal soap or horticultural oil) in the vegetable garden during the bloom period.

Recently I noticed the yellow blossoms are dropping off my tomato plants.  Is there something lacking in the soil that is causing this?

The blossoms are not being pollinated. This can occur when temperatures rise to 90 ° F or above.  Wet weather can also encourage botrytis, a transitory fungal disease, which infects flower stems causing blossom drop. Blossom drop will also occur on plants that are given too much nitrogen fertilizer. Make sure that plants are in full sunlight and evenly watered. As for the blossoms, be patient, as soon as the weather moderates pollination will happen and your plants will begin to produce.

Thinking ahead, I would like to get a jumpstart this fall on a vegetable garden for next season. What is the best way to go about this?  I am interested in making a raised bed. 

You are wise to plan ahead so that your vegetable garden will be ready to use next spring.  Some considerations for choosing a site: full sunlight (8-10 hours is preferable),  good soil drainage, level ground and a water source. Steer clear of areas with trees and shrubs. Do not use treated lumber to build the box; bricks, cinder blocks, oak, cedar or recycled ‘plastic’ wood make excellent substitutions. Begin by delineating the beds with stakes and string or a garden hose. Typical dimensions are 3-4 feet wide and 2-12 inches high, it can be as long as you like.  To kill vegetation in the area, put down newspaper or cardboard, leave it in place and add about 8” of top soil or compost.  A mixture of 70% topsoil and 30% compost makes an excellent growing media.  Analyze the soil before planting and then about once every three years or so.

It is September and my tomatoes still have fruit on them.  I am afraid they will not get the chance to ripen on the vine before the frost. What can I do with all these green tomatoes?

If a light frost is predicted cover the plants in the late afternoon with a floating row cover, and then remove the fabric in the morning. Or you can harvest the fruit and bring the tomatoes indoors to ripen.  Fruits that have started to show some color will ripen satisfactorily indoors.  Wrap the tomatoes individually in paper or place them in a single layer in a paper bag.  Keep them in a cool, moist location. Check them on a regular basis and do not place them in the refrigerator. Green tomatoes can be fried, used in salsa or relish.

This summer I grew a nice collection of herbs in containers that I have enjoyed using when I cook. The thyme, mint, sage and rosemary are still producing and look beautiful. What can I do to protect them this winter? Is it okay to bring them inside?

It can be tricky to overwinter herbs indoors. They do not like hot, dry conditions prevalent in most homes when the heat is turned on. It is best to leave the herbs outdoors in a sheltered location until nighttime temperatures dip into the low forties. At that point bring them indoors and store them in an area that stays cool and away from drafts. Locate them where they will receive strong direct sunlight or place them under “cool white” fluorescent lights. Cut back on watering, water only when the potting mixture feels dry. Periodically check for insects such as spider mites and aphids and treat if necessary. Bring them back outdoors next spring when overnight temperatures climb back into the fifties.

I am a beginner vegetable gardener and have a pretty basic question. What is the best way to water a vegetable garden and how much water should I give my plants?

Vegetables planted in average well-drained soil require about an inch of water per week from rainfall or irrigation (equal to about 62 gallons of water per 100 square feet). Gardens in sandy soil will require a bit more than that in the height of the growing season. Water is crucial during seed germination, after planting transplants, and during flower and fruit production.  Avoid overhead and frequent shallow watering which encourages plant diseases and a shallow root system.  Soaker hoses and drip irrigation are the most efficient means of watering.  They provide water right to the root system and minimize water usage.  When using a hose, use a wand attachment so the water can be directed under the foliage directly to the roots. Water as early in the day as possible to allow the foliage to dry before evening. Add compost or other types of organic matter to increase the water holding capacity of the soil and mulch to conserve soil moisture.

My four raised vegetable beds are overgrown with weeds that I did not clear out in the fall. Is there something I can do now to control the weeds or should I just wait until spring to pull them out?

It is recommended to clean-up vegetable beds in the fall to remove diseased plant material, weeds, and to reduce overwintering places for insects.  But, sometimes time passes and these chores remain undone.  You can get a head start on your vegetable gardening now by cutting the weeds back and then placing several sections of newspaper over the raised beds.  Moisten the paper if doing this on a windy day. Then place several inches of compost and shredded leaves on top of newspaper. This will smother the weeds and help them to break down to improve the soil. Next spring you will be ready to plant directly into the shredded leaves and compost.

This has been another disappointing year for my lima beans.  For the past 2 years, I have planted Dr. Martin lima beans with little success. The vines looked very healthy and blossomed all summer, but did not produce pods or if the formed they quickly dropped from the vine. Can you shed some light on what is going on?  I have been growing limas for years now.

Many home gardeners are experiencing problems growing limas.  There are many contributing factors to the poor performance of lima beans: weather, lack of pollinators, and in some areas stink bug activity.  It has been determined that stink bugs like to feed on lima beans. They usually damage the beans as they develop in the pod but some people think that stink bugs may actually be feeding on the flowers in the early part of the season. Certainly our summers have become hotter the in the past few years. We had record breaking temperatures for a significant portion of past summers. Anytime that we get daytime temps in the 90's and evening temperatures in the 60’s or above for several days the plants grow well, but drop flowers and small pods. Carolina or Sieva types are more heat tolerant than Dr. Martin or King of the Garden large-seeded types. Bush types may also be better suited. Changing what you plant next season certainly is worth trying.

My tomato plants were very healthy this season. I am now noticing some of the leaves turning yellow and then browning. Is this something I should be concerned about? The plants are still producing and I want to make sure I can harvest the rest of the tomatoes.

Extreme heat and typical tomato diseases, like early blight, can challenge tomato growers almost every season. You are fortunate that your tomato plants were healthy.  At this point it doesn’t sound like what is happening to your plants is something to be overly concerned about, especially if the rest of the plant looks healthy. Older leaves naturally turn yellow as they age. As the plant matures, it is even normal for the plant to lose some of its older foliage. This process is called leaf senescence.  If you are noticing any other symptoms such as spots send us a question and photo through 'Ask an Expert'.

Is it safe to use cement blocks to build a raised garden to grow vegetables? I heard about unsafe chemicals in these cement blocks that could leech into the soil and plants.

Cement block, cinder block and concrete block, all are made with cement and fine aggregates such as sand or small stones. Fly ash is also often included. Fly ash is a byproduct of burning coal and so contains heavy metals and other hazardous waste. Labels do not give specific information on exactly what aggregate is used in the manufacture of the block. There is also little research data on this topic. Ultimately, this becomes a personal choice based on your comfort level. If you plan to use block as a raised bed material -- and many people do – and you are concerned about potential risks, you could seal the blocks with polymer paint.  Or you can choose to use another material you are more comfortable with.

Please send us a question at Ask the Experts if you have a vegetable question you would like answered. Digitial photos can be attached to your question.

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