Stake floppy perennials and secure peonies in May.
Image by Sandy Repp

Stake floppy perennials and secure peonies in May.

May

Needle-leafed evergreens (pines) may be pruned back (cut 1/2 of the new candle growth). For more information, see our fact sheet on this topic.


Stake floppy perennials and secure peonies.


Harden off transplants that were started indoors.


Sow seeds of late herbaceous biennials and perennials.


Fertilize early annuals and vegetables. Plants outdoors grow more rapidly than they do indoors, and they may need more fertilizer. For more information, see our fact sheet on this topic.


Weed and then summer mulch your beds and borders. For more information, see our fact sheet on this topic.


Empty the soil in your planters and replace the mix for this year's annuals.


Try successive plantings of gladiolus.


Sow vegetable crops directly into the garden now. For more information, see our fact sheet on this topic.


Prune and divide early flowering perennials after they bloom.


Your roses need tending to. For information regarding rose pruning, see our fact sheet on this topic. For information regarding rose problems, see our fact sheet on this topic. 


Memorial Day is here. You may fertilize your lawn now. For more information, see our fact sheet on this topic.


Prune out the brown or grayish tips of juniper branches during dry weather.


Avoid applying pesticides to herbs that will be used in cooking.


Make sure hoses don't leak, especially where they are connected to the spigot. If necessary, install an inexpensive plastic washer.


When working with power tools and equipment, avoid distraction.


Bring houseplants outside for a summer vacation after May 20. Fertilize them and keep them in the shade or they will sunburn. For more information, see our fact sheet on this topic.


If you see carpet weed and sheep sorrel, have your soil pH tested. Those weeds thrive in acid soil. For more information, fact sheet on this topic. For information regarding Soil Testing, see our fact sheet on this topic.


Look for orange pustules on the underside of hollyhock leaves - sign of rust fungus. Pick off rusted leaves.


Knotweed quickly takes over lawns that have compacted soil. Consider rototilling and renovating the lawn in August or early September. For more information, see our fact sheet on this topic. 

Last updated February 14, 2017