You might think that fall cleanup is self-explanatory: You store some summer stuff and rake leaves, right? But gardeners know there are many tasks this season that prepare the landscape or garden for next year. Fall can be as busy a gardening season as spring itself, but it’s important to know what to do and how, when and why to do it.
Let’s check your knowledge about fall chores with a gardening quiz. Answers and explanations follow.
Note: More than one answer may be correct.
1. Which spring flowers come from bulbs you can plant in autumn? (a) hyacinths (b) petunias (c) daffodils (d) coneflowers (e) hydrangeas
2. What product might you add when planting spring-flowering bulbs for better blooms? (a) sulfur (b) bone meal (c) nitrous oxide (d) high nitrogen fertilizer
3. To build a compost pile you might layer: (a) leaves (b) grass clippings (c) shredded Buffalo News (d) dog waste (e) turkey dinner scraps (f) egg shells
4. You should dig up and store in a non-freezing room: (a) daylilies (b) lily bulbs (c) dahlias (d) cannas (e) Rudbeckias
5. Do these things in October for a healthy lawn: (a) rake off the leaves (b) fertilize (c) cut the grass (d) treat for grubs
True or false?
6. It’s a good time to cut back hydrangeas to make room for new growth in spring.
7. To increase the odds of Endless Summer type hydrangeas (macrophylla) actually flowering, mulch them heavily after the ground freezes – or use a Shrub Cover.
8. Prune needle-type evergreens (firs, spruces, pines) now.
9. Prune fruit trees and hardwood trees as early in October as possible.
10. It’s fine to cut back perennials (a couple of inches above the crown) at this time, and spread mulch over them after the ground is frozen.
What’s wrong here?
Correct the story:
11. Mike had a terrible vegetable garden this season and was told his soil is probably poor and depleted of nutrients. He collects chopped leaves, horse manure and wood shavings from his friend the carpenter. He spreads them over the garden and turns them under to increase soil fertility.
12. Marcy from Amherst loves lilacs and rhododendrons. She is extremely disappointed in her local garden center for the poor quality of the rhododendrons they sold her – worse every season, even though her son put lime down. Next spring she will look for better rhododendrons in the Southtowns.
13. Bob the new landscaper did the job for his dad’s insurance office in Williamsville. It backs up to a woods and faces west so a strong wind hits the building. Bob planted a double row of arborvitae as a wind block, and mulched them really well – about 18 inches up the base of the trunks for winter protection. It looks gorgeous and his parents are recommending him to their customers.
1. (a) and (c).
2. (b) Bone meal or a bulb-booster fertilizer with high middle number (Phosphorus). If you chose sulfur, that would only help to lower soil pH – not the usual need for bulbs. Nitrogen would not be helpful in fall because it pushes new growth.
3. (a, b, c, f). All good except (d) dog waste – it can harbor worms or disease – and (e) meat scraps or fats. They attract animals.
4. (c) and (d); the rest are hardy.
5. (a) and (c). Piled-up leaves or grass clippings contribute to lawn diseases over winter. Do one last cutting. Do not fertilize lawns in October; wait until dormancy in late November. Not time to treat for grubs even if you had them.
6. False: Basically, don’t prune them now. The macrophyllas can bloom on old as well as new (existing) stems. Panicle types rarely need pruning anyway.
7. True: Harsh winters and spring freezes (like last year) ruin many; mulch or cover can help.
8. False: No. Don’t. A cut is a wound – an opening for disease or pests. Prune evergreens when new growth occurs early next season.
9. False: No. Don’t. Fall pruning can cause new growth when the plant is supposed to be going dormant. Prune in late winter or early spring if needed.
10. True. It’s also OK to leave standing any that are attractive or provide seeds for birds.
11. On the right track, Mike, except for the wood shavings. Woody material will eventually decompose but will tie up soil nitrogen while doing so. Keep the wood shavings or chips for the paths only – or mix with manure to build a compost pile.
12. Oh, Marcy: Rhododendrons simply must have acidic soil – a low pH – to thrive. It’s not the nursery’s fault (although upon selling a rhododendron the pro might have discussed the pH issue with you). In Amherst, the Northtowns and much of Buffalo, the soil is generally quite alkaline (although ideally one should test for pH). Definitely don’t use lime; that raises soil pH! Either work at lowering soil pH with sulfur products or live with the pH you have – perfectly fine for lilacs and many other plants.
13. Big mistakes, Bob: You have lots to learn. Sign up for CNLP training through PlantWNY. First, a nearby woods in Williamsville guarantees that deer are nearby, and they adore arborvitae – which can be badly wind damaged as well. Also, a mixed border is less risky than a single species. And mounding mulch up trunks, called “volcano mulching,” is wrong, wrong, wrong. It will cause the trunk to rot. On second thought, Bob, go into your father’s insurance business …
13 correct answers: You’ve been reading this column a long time, or you’re otherwise horticulturally educated.
9–12 correct answers: Good basics; keep learning.
8 or fewer: Everybody starts somewhere. Gardening and landscaping represent a large body of knowledge. Join some gardening classes and don’t give up.
Sally Cunningham is a garden writer, lecturer and consultant.