How to Prune Potato Shrubs

Overview

Potato shrubs are perennials that belong to the solanum or nightshade genus of plants. All potato plants produce blooms and many species also produce edible tuberous roots that we know as the vegetable potato. Potato plants tend to grow rapidly and adopt a shrubby form with either a sprawling or vining habit. Ornamental species grown for their bloom and foliage can easily tolerate trimming into smaller or simply tidier forms, as needed to suit your garden style or space constraints.

Step 1

Prune away dead leaves, spent flower heads, damaged vines or any disease that may be visible regularly throughout the growing season to keep the potato shrub neat looking and healthy. Sever at the point of healthy tissue and compost or throw away the clippings along with any debris that has fallen to the soil below.

Step 2

Create a tree form out of your potato shrub by removing the side stems that emanate from the lower 1/3 to 1/2 of the main stem or trunk. Sever the side stems or branches cleanly, flush with or just 1/8 inch outside of where the two stems meet to prevent gouging into the main stem.

Step 3

Reduce the height and spread of your potato shrub by pruning back the tips of the stems and vines. Conduct this more significant type of pruning in the late spring or summer to resize or rejuvenate the shrub and encourage new compact growth. Remove up to but no more than 2/3 of the shrub's volume in any pruning session. Cut stem by stem or use long-blade shears as desired.

Step 4

Cut back the shrub to the ground in late fall or early spring in cool climates where the top foliage dies back each year with heavy frost. Leave at least 2 inches of the main stem above the soil line and remove all other dead or damaged plant material, composting or discarding it.

Tips and Warnings

  • Prune potato shrubs that have been planted for food production sparingly, if at all, during the growing season. Removing foliage that soaks up the sun to feed plant growth will likely result in a reduction in the size of the potatoes or in the number of potatoes available for harvest. However, removal of dead or diseased foliage and flowers is advisable to keep the plant healthy and pathogen free.

Things You'll Need

  • Pruning shears
  • Secateurs or loppers

References

  • University of Illinois Extension: Ask Extension - Blue Potato Bush
  • University of Illinois Extension: Plant Pallette Ornamental Sweet Potato
  • USDA Plant Database Profile: Solanum
  • University of Minnesota: Pruning Perennials

Who Can Help

  • Logee's Greenhouse Tropical Plants: Solanum wrightii Ornamental Potato Shrub
Keywords: trimming potato shrubs, shaping potato plants, ornamental potato plants

About this Author

An omni-curious communications professional, Dena Kane has more than 17 years of experience writing and editing content for online publications, corporate communications, business clients, industry journals, as well as film and broadcast media. Kane studied political science at the University of California, San Diego.