“Close your books and take out a sheet of paper.”
I haven’t heard the words for decades, but I remember vividly how the teacher’s chilling words struck fear into the hearts of us poor, unsuspecting (and probably unprepared) students when a surprise quiz was announced. It’s easier to laugh about it when you’re no longer a student.
Twice a year, we’ve been featuring a new gardening quiz, not so much to see if we’re paying attention, but because they’re fun. The following can be answered with a few words.
- Does frost help or hinder the autumn color display of trees and shrubs?
- Is the low-temperature threshold for safely picking late-season apples 25, 30 or 32 degrees?
- Can parsnips be left in the garden all winter? Can potatoes?
- Is reusing the same potting mix in next year’s outdoor containers a recommended procedure?
- If seed is collected from heirloom flower and vegetable varieties, will it produce the same results if planted next year?
- If an old-fashioned lilac is pruned in April, will it bloom during the current growing season? Likewise, if a Potentilla is pruned in April, will it bloom the same summer?
- If a tomato plant tag indicates the cultivar produces ripe fruit in 70 days, does that mean 70 days from seeding, or 70 days from transplanting the tomato into the garden?
- When adding leaves or straw around tender perennials or roses for winter protection, should it be done before or after the soil freezes?
- To grow an oak tree from an acorn, is it better to plant the acorn in the fall, or wait until spring?
- Is it better to cut back ornamental grasses like Karl Foerster every year, or are they better left untouched?
- Should fall asters and other autumn-blooming perennials be divided in fall or spring?
- Is the traditional iris-dividing month May, August or October?
- While cool temperatures and bright, sunny days intensify fall foliage colors, frost hinders development as freezing temperatures interfere with the process and speed leaf drop.
- Apples are generally safe left on the tree down to 25 degrees, but may be damaged if temperatures drop lower.
- Parsnip flavor and quality are excellent if left in the ground over winter and dug immediately as soil thaws in spring. Not so with potatoes.
- Yes. High-quality potting mix can be reused for multiple years. Replace one-fourth with fresh, if desired.
- Yes, seed of heirloom flowers and vegetables will “come true” when planted the next year, unlike hybrid seed, which should be bought fresh each year.
- No, old-fashioned lilacs generally won’t bloom if pruned in spring, as pruning removes the preformed flower buds. Potentillas, which flower on newly produced growth, will bloom the same summer if spring-pruned.
- Days to maturity of tomatoes are counted from the date of garden transplanting, not seeding.
- Protective mulch should wait until the top few inches of soil have frozen solid.
- Acorns should be planted in the fall to give them the winter chilling needed to trigger growth in spring.
- Ornamental grasses should be cut to near ground level every spring before new growth emerges from within the clump.
- Autumn-blooming perennials, like fall aster, are best dug and divided in spring.
- Iris are traditionally divided and planted in August. September works fine also.
Don Kinzler, a lifelong gardener, worked as an NDSU Extension horticulturist and owned Kinzler’s Greenhouse in Fargo. Readers can reach him at email@example.com.