Every balcony has the same September moment: the petunias are leggy, the basil bolted, and the pots look like August gave up in them. This plan replants the three planters you already own for fall in one morning, plant by counted plant.
The frost temperatures here come from extension and grower guidance, and the zone dates from the published frost tables; we have not overwintered these exact planters ourselves and don't claim to. The planter sizes are the ones from our balcony garden plan, so if you built that, you own everything but the plants.
Why this plan works
- $22 to $32 all in, because the planters and the herb column cost nothing.
- Every pot gets a count: how many plants, at what spacing, in which spot.
- Each plant comes with the temperature it quits at, so nothing surprises you in November.
- The herb column carries over untouched. It is the cheapest planter on the balcony in fall.
- One watering change, not a new routine.
Which plant gives up first, and when
Fall planting is really a bet on frost dates. This table is the whole bet, from standard extension and grower guidance.
| Plant | Holds to about | What frost does to it |
|---|---|---|
| Ornamental kale | 15 F | Colors up AFTER frost; November is its best month |
| Violas | mid-20s F | Keep blooming; flowers quit in the high teens |
| Pansies | mid-20s F | Same, slightly less cold-tough than violas |
| Garden mum | light frost only | A hard frost ends the flowers |
| Parsley | about 20 F | Keeps going long after basil is gone |
| Chives, thyme | hardy | Die back for winter, return in spring |
Two consequences fall out of the table:
- Where you have a choice of 6-packs, buy violas. They outbloom pansies once nights go below freezing.
- Mint dies back either way. Its pocket in the column is free real estate.
The planting map, planter by planter
| Planter | Size | What goes in | Count and spacing |
|---|---|---|---|
| A. Rail trough | 24 x 8 x 8 in | Pansies or violas | 4 plants, one row, 6 in apart |
| B. Floor box | 24 x 12 x 12 in | Ornamental kale + violas | 1 kale dead center (12 in of spread), 2 violas at each end at 6 in |
| C. Herb column | 16-in three-tier | Parsley, chives, thyme stay | 2 violas in the old mint pocket |
- The kale gets the center of the box because it spreads to a foot and everything else works around it.
- Keep the trough hung inward and the box near the wall, the same 60 lb weight logic as the balcony plan.
When to plant, by zone
Count back three weeks from your average first frost. That is the whole calendar.
| Zone | Plant by |
|---|---|
| 5 | Sep 20 |
| 6 | Oct 1 |
| 7 | Oct 15 |
| 8 | Nov 1 |
Check your own zip code on the Old Farmer's Almanac frost tool; the bands above are averages, not promises.
June's rule: plant fall pots three weeks before the frost date, not the week the mums show up at the store.
The mum question
Never plant the mum. It blooms for about 3 weeks, and digging it into the box costs you the kale's spread for a tenant that leaves by Thanksgiving.
- Set a $10 nursery-pot mum on the floor beside the box, still in its plastic pot.
- Compost it in November without disturbing a single root in the box.
- Pet note: chrysanthemums are on the ASPCA toxic list for dogs and cats (vomiting, drooling). If a pet uses the balcony, the mum stays up off the floor or stays at the store. Pansies are on the ASPCA non-toxic list; ornamental kale is on neither list, and we won't claim otherwise.
Copy this plan
| Item | Where it goes | Price | Running total |
|---|---|---|---|
| Two 6-packs pansies/violas (10 plants) | Trough A + box ends + column pocket | $10 | $10 |
| 1 ornamental kale | Box B, center | $6 | $16 |
| 8-qt bag container mix | Top-up, all three | $6 | $22 |
| Garden mum in nursery pot (optional) | Floor, beside box B | $10 | $32 |
Prices are typical US retail, rounded; prices vary. No fall fertilizer: growth is too slow to use it, so the slow-release bag stays in the closet.
1. Pull the summer annuals, keep the herbs
Pull the spent petunias and the bolted basil, roots and all. Parsley, chives and thyme stay exactly where they are.
2. Refresh the top of the mix
Scrape off the top 2 inches of tired mix and top up with fresh. Full soil swaps are a spring job, not a fall one.
3. Plant to the map
Work the table above: 4 in the trough, kale plus 4 violas in the box, 2 violas in the mint pocket. Firm each plant in with your thumbs, no air pockets.
4. Water until it drains
Water each planter until it runs from the drainage holes. This settles the mix around the new roots.
5. Set the mum beside, not in
The nursery pot sits on the deck boards beside the box. That is its whole installation.
6. Know your cold-snap move
When the forecast dips below 20 F, slide the trough against the wall and drop an old sheet over the box overnight. That single move buys the violas weeks.
The one watering change
Same finger test as summer: water when the top inch is dry.
- Expect weekly to twice weekly instead of daily. Cool air and short days slow everything down.
- Skip watering the day before a hard freeze; wet mix freezes harder around roots.
The kale looks better in November than it does the day you plant it, which is the quiet joke of fall planters. This swap fits the Saturday before a frost warning, the last warm morning of October, or the week the porch starts feeling bare. If the indoor half of the season is calling too, the fall living room under $100 runs the same palette inside, and stopping at the $22 version of this plan still counts as done.
