logo4.gif - 6940 Bytes

 THC Home

 Club Events & Activities
    THC Calendar
    Meeting Information
    THC Past Activities:
      Reports & Photos

   Current Newsletter
   Past Newsletters

 Become a Member

 From our Gardens
    Member's Photos
    Member's Tips

 Gardening Info & Resources
   Online Resources
   Online Sources
   Local Sources
   Plant Societies
   Public Gardens

 About the Club
    Club Leadership
    Club History
    Constitution & By-Laws

 Join our Email Group (listserv)

title11.jpg - 14479 Bytes

What to Do When

The collective wisdom of the 200+ members of the Takoma Horticultural Club email list.

January/February   March  April  May/August  August/September 


What you CAN do these months:

  • Leaf removal
  • Moving rock and soil, if unfrozen
  • Building structures
  • Order from catalogues
  • Plant or move deciduous (leaf-dropping) woody plants, as long as the ground's soft enough. This can also be done in March, but definitely is best done before the new leaves appear.
  • Start seeds indoors.
What you SHOULD do these months:
  • Nothing. Oh, maybe some fantasizing about spring.


  • Clean-up. Remove leaves from borders, being careful not to step on emerging bulbs or perennials. Remove any dead perennial foliage you left in place over the winter. Remove dead ornamental grasses, preferably before March 15 so as not to damage newly emerging foliage. Liriope should be given a haircut if it's brown or damaged by winter.
  • Pruning. None of these necessarily need pruning but if you do prune, March is the best time to prune summer- or fall-blooming shrubs like roses, spireas, also nandina, euonymus, hollies, pyracantha, laurels, and late-blooming hydrangeas like Tardiva or Oakleaf. (Mophead and lacecap hydrangeas don't need pruning unless they're too large but should be pruned immediately after blooming, if pruned at all.) Deadwood can be removed from shrubs and trees anytime.
  • Start seeds indoors.
  • Lawn Care. For sunny lawns with a history of crabgrass, apply preemergent crabgrass killer when the dogwoods bloom. Application when the forsythia bloom is no longer recommended - too early. If you're also seeding this spring, use a crabgrass treatment likeTupersan or any other product specially designed to allow the germination of seed, or plant grass seed three weeks after application of the herbicide. Spring is not the best time to fertilize your lawn - it promotes weeds and excessive blade growth at the expense of roots, and causes the greatest damage to the Chesapeake Bay. If your lawn really needs fertilizer this spring, an organic, slow-release fertilizer is much less likely to cause these problems. Seeding of lawns is best done in August-September, but you can also seed in the spring - in March or April.
  • Tree care. If snow has left conifers bent over, stake them now and try removing stakes after two months to see if the plant has righted itself.
  • Planting. March is a fine time to plant anything that's hardy to freezing temperatures, as long as the ground's not frozen. However, most plants aren't available in nurseries until at least April.
  • Plant dividing. Divide ornamental grasses, as needed (usually every 3-5 years), also summer or fall-blooming perennials like sedum (if the sedum got so big they flopped over last season).
  • General Care. Sometime in late winter or early spring after perennials are cut back, apply 1 to 2 inches of compost, leaf mold or Leafgro to beds and at the base of trees (but keep compost away from the trunks of trees and shrubs!)

    If scale, fungus or insect nests were seen last season, spray affected plants with dormant horticultural oil as soon as temperatures remain above 50 degrees during the day. Spraying now reduces the need for treatments during the growing season and is kinder to the environment.

  • Vegetable Gardens. Prepare for spring planting as soon as ground is friable by rototilling 7-8" deep, adding liberal amounts of compost and manure, fertilizing those areas to be planted immediately with 5-10-5. Sow cool-season vegetables and herbs.


  • Lawn Care. Use slow-release organic fertilizer if lawn wasn't fertilized last fall. Also good time to apply high calcium lime to raise the pH.
  • Trees/shrubs
    • Early April, prune deciduous trees and shrubs, except those that bloom in spring and early summer.
    • Cut back buddleias and caryopteris shrubs to 12-18".
  • There's disagreement over whether April or September is the best time to plant trees and shrubs, but both are excellent times and now is a much better time to plant than after it gets really warm in May or later.
  • Perennials. Put cages or other support around peonies as they emerge.
    • Divide or move existing perennials and plant new ones now before they get too large and the temperatures get hot.
    • Chop down dead foliage of ornamental grasses if it wasn't done in March.
    • Plant new ornamental grasses and ground covers.
  • Bulbs. Plant summer-blooming bulbs.
  • General Care. Mulch your borders if you didn't do it last month, 1 to 2 inches, being careful not to put any mulch against the trunks of trees or shrubs

MAY through AUGUST

General Growing Season Gardening Jobs

  • Watering
    • One of the 2 primary tasks for gardeners from May until it cools down in the fall, especially if you want plants you've bought or moved this spring to survive their first summer.
    • Plants in pots and hanging baskets require frequent watering, often daily, plus fertilizer twice a month until mid-summer.
    • And it's the duty of every gardener to notice rainfall or the lack thereof and water during periods of sustained drought. But don't be fooled by those worthless thunderstorms; only rains that soak the ground count.
  • Weeding is the other primary gardening task during the growing season. If you mulched last month like we told you to, the job will be easier, but there's no way around it - to garden is to weed. Keep on top of it and make sure to remove them before they set seed. And weeding is easier to do when the ground is wet.
  • Shrubs
    • Prune azaleas after flowering if they're too large.
    • Deadhead spent rhododendron blossoms to promote next year's flowering, pinching them off at their base and being careful not to damage the emerging new growth.
    • Deadhead spent lilacs, likewise to promote next year's flowering.
  • Annuals should be planted outdoors after May 1, our latest average frost day. Feed with liquid fertilizers twice a month through the season.
  • Perennials. Cut down late-blooming perennials by half for denser flowering, shorter height, prevention of flopping or the need to stake. Likely candidates are: asters, sedum 'Autumn Joy' in less than full sun, purple coneflowers, mums, obedient plant, salvia and campanula. Do this once more around Memorial Day, but definitely no later than July 4. Mums are often cut back three times in total between early May and early July.
  • Lawns. Set your mower to 3-4 inches, the higher the better, and cut frequently enough so that no more than 1/3 of the blade is cut at each mowing, for better turf health.


  • Fertilizer, fungicides and insecticides. Do not apply them during the dog days (over 80 degrees) - it could do more harm than good. And whatever the temperature, don not apply them to plants stressed by lack of water, so you may need to water thoroughly first.
  • Watering. Spring-blooming woody plants are setting seed now, so make sure they are watered. And by late August, most plants are storing water for the winter and benefit from weekly watering (deep watering at the base of the plant). Any perennial planted this year needs weekly watering in August and through the fall, as well.
  • On vacation? Move pots to a shady spot, and get someone to water them while you are gone
  • Planting. In August, wait out the 90-degree spells before planting, and waiting for a cloudy day is best, or at least do the work in the evening. Water well and check at least twice weekly for water needs, even if they plants are famously drought-tolerant.
  • Lawn Care. August 15-October 15 is the ideal time to seed lawn in our area. Unless you have added lime in the last 3 years or a test confirms your soil does not need it, apply lime first with an organic fertilizer, then seed.
  • General
    • Late August is a good time to dig and divide daylilies and irises.
    • Whole Garden - September is the best time to assess your whole garden for changes and additions.
    • Fall Clean-up can start in September by cutting off flower stalks and ugly or diseased foliage. Leave seedheads on black-eyed-susans for the goldfinches.
    • Fall Annuals. Late September into October is a good time to buy pansies and mums, which both need at least a half day sun (and mums benefit from more than that.) Violas are fine with less than half a day, by the way.

For questions about the functioning of the website, please contact our webmaster: webmaster@takomahort.org