Tag: Horticulture

Dividing Peonies in Fall:

Peonies are a favorite perennial of gardeners because of their beauty and low maintenance. In Kansas, peonies provide a beautiful display of flowers each spring around Memorial Day. Though peonies can be left in place indefinitely, many gardeners wish to increase their plantings and use a process known as division to accomplish this. Keep in mind, however, that peonies often take about three years to return to full bloom and size after division.

Fall is the traditional time to divide these plants. Peonies are essentially dormant by mid-August even though the foliage is still green. The first step in division is to remove the foliage. Then dig out the entire plant. Shake and wash off as much soil as possible so that the pink buds or “eyes” are visible. Peony roots are tough, and a sharp knife is needed to cut the roots into separate pieces. Make sure each division has three to four buds. Make sure the location chosen for planting receives at least a half-day of full sun. However, the more sun, the better. Space the plants so that there is at least 2 feet between dwarf types and 4 feet between the standard types.

Follow the same rules for planting these divisions as you do for new plants. Make sure the pink buds are about 1 inch below the soil surface. If they are set more than 2 inches deep, flowering may be delayed or completely prevented. As you set the plants, firm soil often as it is added around the plant. If the soil is not firmed, it can settle and pull the plant down with it. Water in well after planting and water as necessary through the fall and winter to keep the soil moist.

It is often a good idea to add mulch to the new planting to protect it from heaving. The alternate freezing and thawing that commonly occurs during Kansas winters can “heave” weakly rooted plants out of the ground. Add a mulch of straw, leaves, compost or other material after the soil freezes. Remember, it is not the cold that harms these plants but the alternate freezing and thawing of the soil.

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

Fertilizing Strawberries

Strawberry beds might be done producing for the summer, but that doesn’t mean we can forget them. An August application of nitrogen on spring-bearing strawberries is important in order to increase the number of strawberries produced next spring. Plenty of daylight and warm temperatures during June, July and August promotes the growth of new runners, or daughter plants. As daylight hours dwindle and temperatures grow cooler in September and October, fruit buds for the next year’s fruit crop develop. To get a good berry crop next spring, it is important for strawberry plants to be vigorous during this period of fruit bud development.

Nitrogen, applied mid-August, will help promote fruit bud development. A general application rate is ½ to 3/4 pound of actual nitrogen per 100 feet of row. The nitrogen may be in the form of a fertilizer mixture such as ammonium phosphate or 12-12-12, or in a fertilizer containing only nitrogen such as urea or ammonium nitrate. Some specific examples would include:

Iron + (11-0-0) at 6 pounds per 100 feet of row.

12-12-12 at 5.5 pounds per 100 feet of row.

Nitrate of Soda (16-0-0) at 4 pounds per 100 feet of row

Ammonium sulfate (21-0-0) at 3 pounds per 100 feet of row

Urea (46-0-0) at 1.5 pounds per 100 feet of row

On sandy soils, the rate may be increased by about a half. After spreading the fertilizer, sprinkle the area applying at least a half-inch of water to move the nitrogen into the strawberry root areas.

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

Dealing with Chiggers

Chiggers are mites, not insects. And like all mites, the adults have eight legs.  However, the larva only has six legs.

Though the bright red female adult is tiny (about 1/20th of an inch) the larva is much smaller (about 1/150th of an inch). Only the larvae are parasitic and attack animals. The larva injects digestive juices into the skin, which causes a rapid swelling. In the center of the swelling is a “feeding tube” from which the chigger sucks out liquefied skin cells. Feeding usually continues for 2 to 4 days.

Protection from chiggers uses two approaches. The use of a repellent can discourage chiggers from attacking. The most effective repellents are Deet and permethrin. Both chemicals are applied to your clothing. The second approach seeks to reduce chigger populations. Keeping the lawn mowed regularly can help, but large populations may require the use of an acaricide. Effective products include bifenthrin (Talstar, Hi-Yield Bug Blaster II, Hi-Yield Bug Blaster Bifenthrin, and Ortho Lawn Insect Killer Granules), cyfluthrin (Tempo 20, Bayer Vegetable & Garden Insect Spray) and carbaryl (Sevin).

For more information go to: https://www.bookstore.ksre.ksu.edu/pubs/MF2107.PDF

By: Cassie Homan