Don’t let wet soil spoil your annuals

By

Community

July 9, 2019 - 10:52 AM

Kansas peonies are among the annual flowers that may be affected by abnormally wet soil this year. WIKIPEDIA.ORG

We’ve had an unusually rainy spring and summer.

Our soils have been saturated for several weeks. 

You may think that watering won’t be needed for quite some time since soil moisture levels remain high. However, watering may be needed much sooner than you think. 

Excessive rain can drive oxygen out of the soil and literally drown roots. Therefore, as we enter hotter, drier weather, the plants with damaged root systems may be more susceptible to lack of water. Don’t forget to check your plants for signs of wilting or leaf scorching and water as needed.

The excessive rainfall has also depleted our soil of nitrogen. If your annual flowers haven’t been overly impressive yet, they may need a shot of fertilizer. 

Annual flowers have been bred to flower early and over a long period of time. Providing nitrogen through the growing season (sidedressing) will help maintain flower display. A high nitrogen fertilizer applied every four to six weeks is helpful during a rainy summer or if flower beds are irrigated. 

Common sources of nitrogen-only fertilizers include nitrate of soda, urea and ammonium sulfate. Use only one of the listed fertilizers and apply at the rate given:

• Nitrate of soda (16-0-0) – Apply three-quarters pound of fertilizer per 100 square feet

• Urea (46-0-0) – Apply one-quarter pound of fertilizer per 100 square feet

• Ammonium sulfate (21-0-0) – Apply one-half pound of fertilizer per 100 square feet

If you cannot find the above materials, you can use a lawn fertilizer that is about 30% nitrogen (nitrogen is the first number in the set of three) and apply it at the rate of one-third pound per 100 square feet. Do not use a fertilizer that contains a weed killer or a weed preventer.

Removing spent flowers or “deadheading” will help some plants bloom more profusely. Annuals focus their energy on seed production to ensure the species survives. If old flowers are removed, the energy normally used to produce seed is now available to produce more flowers. Deadheading is as easy as pinching the plant between the thumb and finger, but tough, wiry stems will require the use of scissors or pruning shears. 

Plants that do increase blooms in response to deadheading include hardy geraniums, coreopsis, some petunias, marigolds, snapdragons, begonias, some roses, zinnias, sweet peas, salvia, blanket flower and yarrow.

There are some “self-cleaning” plants on the market. These plants drop their spent flowers and bloom again and do not require manual deadheading. In many cases they are sterile varieties — bred not to produce seeds. The petunia and rose varieties that are “self-cleaning” continue to excel in the home garden market because of their low maintenance and blooming power.

If you need help with any horticulture topic, give me a call. 

Related