K-State horticulture expert gets you ready for planting this year’s crop

It’s still nearly three months before Kansas gardeners begin to put tomato plants into the ground. Kansas State University horticulture expert Cynthia Domenghini says that’s an opportunity for gardeners to set themselves up for a bountiful season.

“Most of the varieties available to home gardeners are indeterminate,” Domenghini said.

Indeterminate plants are traditional tomatoes that never stop growing. They are capable of producing fruit throughout the season unless disease stops production or frost kills the plant.

Domenghini said gardeners will benefit from choosing tomato varieties with strong disease resistance characteristics.

“Gardeners with limited space will likely prefer indeterminate or determinate types to stretch out the harvest season,” Domenghini said. “If there is space, you may want to grow a combination of all three, with the determinates used to produce a large harvest for canning or tomato juice, and the remainder for fresh eating.”

In Kansas, tomatoes are generally planted in early- to mid-May, or when daytime temperatures are above 70 degrees Fahrenheit and the state has passed the frost-free date. In some areas, such as the northwest part of the state, conditions might not be right for planting tomatoes until the middle of May or a bit later, according to Domenghini.

Even though indeterminate varieties produce fruit throughout the season, “our hot Kansas summers often cause a dry spell in production,” Domenghini said.

Tomatoes are less likely to set fruit when night temperatures remain above 75 F and day temperatures are above 95 F. Hot, dry winds make the situation worse, Domenghini said.

Tomato trials

Each year, Kansas Master Gardeners plant and rate a number of tomato varieties. Domenghini noted that a subsequent trial is conducted by a colleague with the University of Missouri extension service.

Results of trials conducted by Kansas’ Master Gardeners vary by county. Interested persons are encouraged to contact their local extension office for more information on varieties that perform well in their area.

Domenghini said the University of Missouri trials also give valuable information on varieties that perform well in this region. The data from Missouri’s extension service showed that the top 10 varieties (based on pounds of fruit harvested per plant) are:

• Amish Paste.
• Beefmaster.
• Beefsteak.
• Big Beef.
• Celebrity.
• Chef’s Choice.
• Early Girl.
• Florida 91.
• Jet Star.
• Summer Pick.

Domenghini and her colleagues in K-State’s Department of Horticulture and Natural Resources produce a weekly Horticulture Newsletter with tips for maintaining home landscapes and gardens. The newsletter is available to view online or can be delivered by email each week.

Interested persons can also send their garden and yard-related questions to Domenghini at [email protected], or contact your local K-State Research and Extension office.

To stay healthy, sometimes trees need a little help in the form of a trim. Pruning is an essential maintenance activity to promote tree health, safety, and aesthetics. Since trees are large, long-living plants in our landscape, pruning throughout the life of a tree can have a significant impact on how it functions in the landscape and how long it survives. Pruning while a tree is young can have exponentially beneficial results for long-term tree health, maintenance requirements, and beauty.

Because no two trees are the same, pruning is both an art and a science. Research has helped advance our understanding of tree physiology and response to pruning activities, improving techniques and outcomes. Deciding which pruning cuts to make depends on many unique factors, such as plant species, age, reasons for pruning, and desired outcome.

Before making a pruning cut, it is important to assess the entire tree and surrounding site conditions that influence the tree. It is also critical to determine your objectives for pruning. Every pruning cut, large or small, should have an explicit purpose and advance the tree toward the identified goals.

There are many reasons for pruning a tree, including safety, health, and appearance.

Prune for safety

Pruning for safety involves pruning branches that interfere with human activities or pose a threat. You can improve safety by removing limbs that block traffic sight lines or branches over sidewalks and trails that impede pedestrian traffic. Additionally, broken limbs in the canopy pose a fall risk and should be removed.

Prune for tree health

Pruning for health includes the removal of branches that cross or rub with others to minimize self-wounding. Pruning trees for structural integrity is an effective way to increase safety and promote tree health. One of the most common structural concerns is co-dominant leaders. Trees with two or more dominant leaders develop structurally weak branch angles that threaten to split under the weight of the canopy. Corrective pruning should be done to encourage a single leader. Pruning dead or diseased limbs removes disease pathogens from the tree and should always be an objective of a pruning regime.

Prune for appearance

Pruning for aesthetics turns the focus toward human preferences. The desired appearance is a subjective analysis, however, pruning decisions made for looks should still adhere to proper pruning techniques and prioritize the health and safety of the tree.

When should trees be pruned?

In the Midwest, the late dormant season is the optimal time to prune deciduous trees. While dormant, deciduous trees have shed their leaves, making it easier to assess the overall form of the tree and make pruning choices related to structural integrity easier. By pruning just before spring, trees can better allocate energy resources toward producing leaves that will remain on the tree throughout the growing season. They also dedicate energy to sealing the wounds created by pruning. Pruning branches full of leaves diminishes the tree’s capacity to photosynthesize and replenish carbohydrate reserves. Finally, pruning in later winter means that opportunistic insects and disease pathogens are also dormant, reducing the risk of infection.

How to make a pruning cut

Once you decide a pruning cut is necessary, proper technique is required.

Preserving the branch bark collar is essential to wound sealing. The branch bark collar is a swollen or raised strip of bark at the intersection of the branch and the trunk of a tree. Pruning practices of the past that include flush cuts removed the branch bark collar and are no longer recommended.

Make pruning cuts just outside the branch bark collar and have a smooth finish. If larger branches are being removed, a three-point pruning cut is recommended to avoid ripping the bark as the limb falls during the pruning activity under the weight of the branch.

Pruning is an ongoing maintenance activity, and trees should be assessed annually for pruning needs. Being consistent with assessment and action can help minimize the workload for pruning and minimize stress response in trees. If mature trees need pruning, it is best to consult with a professional arborist. Safety should always be the top priority. Pruning activities that require lift equipment or power tools should be performed by a professional arborist.

For many gardeners, midwinter is a time for pacing the floor and waiting for the weather to break. There’s been plenty of time for indoor projects, but they’ve either been completed or their appeal has faded. Well, here’s an indoor gardening project that needs your attention; sorting through and discarding out-of-date garden seeds.

If you’re like many gardeners, it’s a bit difficult to discard leftover seeds that may still be useable. How long you can keep leftover vegetable seeds depends on several factors, including the kind of vegetable seeds you have and how you’ve stored them over the past year or two. Maintaining ideal seed storage conditions in your home is impractical; but, if you’ve kept the seeds fairly cool and dry, they may still be good enough to plant.

As a rule, most vegetable seeds will remain useable for at least two or three years. There are exceptions; onion, parsley, parsnip, and lettuce seeds loose viability quickly and should be replaced every year. If you’ve been keeping sweet corn, okra and pepper seeds they’ll still be good after two or three years. Squash, watermelon, cucumber, muskmelon and tomato seeds will last up to four years.

No matter how well seeds are stored there’ll always be some uncertainty about their ability to produce a good stand of healthy seedlings. For that reason, it’s a good idea to do a seed test. Select ten seeds at random from the seed packet (do this for each seed lot). Fold the ten seeds inside a moistened paper towel and seal them in a plastic bag. Keep the seeds in a warm room and check them one week later for germination. If four or more of the seeds out of the ten have germinated and are showing signs of good growth the packet of seeds is still good enough to use; otherwise, discard the seeds and buy new seeds for your garden.

Kansas State Reasearh & Extension