Tag: Vegetables

Soil Temperature and Vegetables

One of the most neglected tools for vegetable gardeners is a soil thermometer. Soil temperature is a much better measure of when to plant than air temperature or the calendar. Planting when soil is too cool can cause some seeds to rot and transplants to not root successfully.

A number of vegetables can germinate and grow at cool temperatures. For example, peas will germinate and grow well at a soil temperature of 40 F. Though lettuce, parsnips, and spinach can sprout at a soil temperature of 35 F, they prefer at least 45 F for best germination and growth. Radishes also do well at a soil temperature of 45 F. Even if the seeds of these cool- season crops are planted below the recommended soil temperature, the seed will rarely rot.

Warm-season crops such as tomatoes, sweet corn and beans are different. They prefer at least 55 F for germination (or transplanting), but others such as peppers, cucumbers, melons and sweet potatoes need it even warmer, about 60 F. If planted when soils are too cool, they likely will rot before germinating.

To take the temperature of your soil first, use a metal soil thermometer, which is sold in many garden, auto parts and hardware stores. Take temperature 2.5 inches deep at about 10 to 11 a.m. Temperature variations throughout the day and night affect soil temperature, with lowest readings after dawn and warmest around mid-afternoon. The late-morning reading gives a good average temperature. Be sure to get a consistent reading for four to five days in a row before planting, and make sure a cold snap is not predicted.

By: Cassie Homan

Garlic Planting Times

October is a good time to plant garlic if you want large quality cloves next summer. Apply 3 pounds of 10-10-10 fertilizer per 100 square feet and mix into the soil before planting or fertilize according to soil test. Plant individual cloves point up and spaced 6 inches apart and 1 to 2 inches deep. The larger the clove planted, the larger the bulb at harvest. Water in well and mulch with straw to conserve soil warmth and encourage good establishment.

Harvest will not occur until next summer. Test dig when the lower 1/3 of the foliage is yellow. If the cloves have segmented, it is time to harvest. If they haven’t segmented, wait another week or two.

Inchelium Red has an excellent storage life and Chesnok Red isn’t bad.  Others you can try include Armenian, Music, Purple Glazer, Carpathian Mountain, Metechi, China Strip, Ajo Rojo, Asian Tempest and Silver White.  Kansas has the type of climate that allows us to grow a wide variety of garlic types well.

By: Cassie Homan

Harvesting Winter Squash:

Summer squash such as zucchini and crookneck squash are harvested while immature. However, winter squash such as acorn, hubbard and butternut are harvested later, in the mature stage, after the rind is tough and seeds have developed. We normally think September is the time that winter squash is harvested. Harvesting too early leads to fruit that shrivels and rots.

There are two main characteristics that help tell us when winter squash are mature: color and rind toughness. Winter squash change color as they become mature. Butternut changes from light beige to deep tan.  Acorn is a deep green color but has a ground spot that changes from yellow to orange when ripe.  Gray or orange is the mature color for hubbard.

A hard, tough rind is another characteristic of mature winter squash. This is easily checked by trying to puncture the rind with your thumbnail or fingernail. If it easily penetrates the skin, the squash is not yet mature and will lose water through the skin — causing the fruit to dry and shrivel. Also, immature fruit will be of low quality. The stem should also be dry enough that excessive water doesn’t drip from the stem.

Winter squash should be stored cool with elevated humidity. Ideal conditions would be 55 to 60 degrees F and 50 to 70 percent relative humidity. Under such conditions, acorn squash will usually last about 5 to 8 weeks, butternuts 2 to 3 months and hubbards 5 to 6 months.

By: Cassie Homan

Foliar Disease of Tomatoes

This year has been very wet and humid. In some ways this can benefit our plants. However, it can also encourage disease. Two common leaf-spot diseases appear on tomato plants, septoria leaf spot and early blight, both appear as brown spots on tomato leaves.

                               Septoria Leaf Spot

Septoria leaf spot usually appears earlier in the season than early blight and produces small dark spots. Spots made by early blight are much larger and often have a distorted “target” pattern of concentric circles. Heavily infected leaves eventually turn yellow and drop. Older leaves are more susceptible than younger ones, so these diseases often start at the bottom of the plant and work up.

Mulching, caging, or staking keeps plants off the ground, making them less vulnerable. Better air circulation allows foliage to dry quicker than in plants allowed to sprawl. Mulching also helps prevent water from splashing and carrying disease spores to the plant.

If you know you have had one of these diseases in the past, rotation is a good strategy. It is too late for that now, but keep it in mind for next year. Actually, rotation is a good idea even if you have not had problems in the past. If you have room, rotate the location of the tomatoes each year to an area that has not had tomatoes or related crops (peppers, potatoes, eggplant) for several years.

If rotation is not feasible, fungicides are often helpful. Be sure to cover both upper and lower leaf surfaces, and reapply fungicide if rainfall removes it. Plants usually become susceptible when the tomato fruit is about the size of a walnut. Chlorothalonil is a good choice for fruiting plants because it has a 0-day waiting period, meaning that fruit can be harvested once the spray is dry. Chlorothalonil can be found in numerous products including Fertilome Broad-Spectrum Landscape and Garden Fungicide, Ortho Garden Disease Control, GardenTech Daconil and others. Be sure to start protecting plants when the disease is first seen. It is virtually impossible to control this disease on heavily infected plants.

If chlorothalonil doesn’t seem to be effective, try mancozeb (Bonide Mancozeb Flowable). Note that there is a five-day waiting period between application and when the fruit can be harvested. You may wish to pick some tomatoes green just before you spray if you use Mancozeb as the tomato fruit will ripen inside.

More information on foliar disease, follow this link: https://www.bookstore.ksre.ksu.edu/pubs/L721.pdf

By: Cassie Homan

Plant Some Squash!

If spring got away from you and you didn’t get all your seeds planted, don’t fret! There is still plenty of time to plant squash. Now is a great time to plant pumpkins and winter squash so they don’t try to mature fruit during the heat of summer but rather in early October. Fruit that matures during hot weather may shrivel and lose quality. Also, planting at this time will allow these plants to avoid the first generation of squash bugs that can kill plants planted earlier.

​These plants take up a lot of room so place a seed or two ever 2 feet apart in the row with about 8 to 10 feet between rows. Seeds should be planted 3/4 to 1 inch deep. Keep watered until the plants emerge which usually takes about a week. Gradually back off watering as the plants become established. Winter squash and pumpkins love the heat and do well during the summer.

By: Cassie Homan