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More recent landscape questions and answers

Horticulture

Blue wildflowers

QuestionI want to plant blue wildflowers around a pool to make the water seem even bluer. What would be the best native plants for this effect?

Answer Chicory

Blue as a flower color in nature is rather rare which is one of the reasons blue cultivated flowers are so highly sought after. Also, since most wildflowers are perennials their bloom span is limited in duration and somewhat sparse when compared with annual flowers. Chicory (Cichorium intybus) is native to Missouri and has beautiful light-blue flowers that appear in late summer.

As an alternative you might want to consider blue-flowered perennials such as balloon flower or aster. If you don't mind replanting them each spring annuals such as blue salvia or blue shades of petunia would provide a season-long effect.

David H. Trinklein
Department of Horticulture

Soil from plant containers

QuestionWhat should I do with soil after I remove the plants from my containers?

AnswerIt is recommended that the potting soil be added to the compost pile or to native garden soil and not reused in containers the following season. This is because the mix may be harboring fungal pathogens and because it loses its structure over the season with repeated watering. Some gardeners report success with reusing the old soil but only after mixing it with new soil (at about a 50/50 rate) and using the mixture.

Jay Chism
Agronomy Specialist

Sterilize plant containers

QuestionWhat should I use to clean and sterilize my plant containers before reusing them?

AnswerUse a weak solution of 10 parts water and one part chlorine bleach to scrub out the inside after the soil has been removed (this is a 10 percent bleach solution). This same solution can be used to sterilize tools and work areas too.

Jay Chism
Agronomy Specialist

Annuals in containers over winter

QuestionShould I remove annual flowers or other annual plants from containers prior to winter storage?

AnswerAt the end of the growing season and after a killing frost, annual flowers and vegetables should be removed from their containers. The vegetation should be added to a compost pile. Containers should be cleaned at the end of the season to rid them of pathogens before storing.

Jay Chism
Agronomy Specialist

Storing plant containers outside

QuestionIs it okay to store all my plant containers outside over the winter?

AnswerSmall plastic or metal containers need to be moved to a protected outdoor location or something like an unheated garage. If left outdoors, these containers should be turned upside down. Winter freezing and thawing may crack the containers if water is left in them. Wooden containers should not have the soil removed as the wood may dry out and shrink if empty.

Store clay containers indoors over winter where temperatures will not fall below freezing. Because clay is porous, it will hold moisture, and can crack when water in the pot freezes and expands.

Jay Chism
Agronomy Specialist

More horticulture questions and answers

Updated 3/6/08

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Your farm's bobwhite potential
Besides being a desirable wildlife species for recreational hunting, bobwhite quail also play an important role within forest, grassland and agricultural ecosystems.

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Answered

QuestionI live in Missouri and would like to grow prickly pear cactus in my yard. Where can I find information on how to do this in our climate and soil conditions?

AnswerRead the answer from David H. Trinklein, Department of Horticulture.