Chrysanthemums — garden mums — bring a blaze of colour in yellow, bronze, pink, purple and white to a Zone 13 garden in the months when many flowers are fading. They are short-day plants, flowering as days shorten, and with winter lows above 60°F and no frost at all, Zone 13 gives them a season in the coolest months rather than the crisp autumn display they give in colder zones. That display is still generous: mums flower for weeks if you deadhead them, and they are superb cut flowers.
The keys in Zone 13 are timing and pinching. Plant in the cooler months, pinch young plants to keep them bushy, and stop pinching well before flowering so buds can form. This guide covers when to plant chrysanthemums in Zone 13, with the soil, spacing, sun, water and care they need. Use the Zone 13 planting calendar to see what else to sow alongside it.
Zone 13 at a glance
USDA Zone 13 has average winter lows of above 60°F and is frost-free year-round — there is no last or first frost date to plan around. Plan by heat and by the wet and dry seasons instead: heat lovers grow year-round, while cool-season crops only succeed in the coolest months. These are zone averages, not promises for any one garden, so check your local extension service for your area.
| Detail | Zone 13 guidance |
|---|---|
| Last / first frost | None — Zone 13 is frost-free year-round |
| Average winter low | above 60°F |
| Days to germination | 7–14 days |
| Days to maturity | 90–120 days |
| Sowing | Start indoors or direct sow |
| Transplanting / planting out | Coolest months only; best results in the planting window above |
| Harvest | Flowers 90–120 days after sowing/planting; pick regularly |
| Sun | full sun |
| Soil pH | 6.0–7.0 |
| Spacing | 12–18 inches |
| Water needs | moderate |
When to plant chrysanthemums in Zone 13
In Zone 13, plant chrysanthemums in the coolest months, roughly November to February, so they establish while nights are at their mildest and flower before the hot season peaks. There is no last or first frost date to plan around — Zone 13 is frost-free year-round with winter lows above 60°F — so work from the calendar and the cool season instead. A hot-season planting will struggle: plants stretch, flower sparsely and are quickly finished by heat. Chrysanthemums take 90–120 days to maturity, so a November planting can flower in the cool season. Check your local extension service for the best planting windows in your area. Frost dates are zone averages — check your local extension service before you commit to a date.
Because chrysanthemums are perennials, a plant that survives its first hot season may return and flower again next cool season, especially where it gets afternoon shade and steady water. Keep a note of your planting date and first flowers; after one season you will know exactly which weeks suit chrysanthemums best in your own garden. Cut plants back after flowering and mulch over the crown for the hot season rest.
Starting chrysanthemums in Zone 13
Chrysanthemums can be started indoors or sown direct, and in Zone 13 starting indoors gives you far more control. Sow in trays or small pots in a cool, bright spot — seeds germinate in 7–14 days — and grow seedlings on until they have several true leaves and are sturdy enough to handle. Harden seedlings off for a week in a sheltered spot before planting out. Nursery-bought plants are a sensible shortcut where the cool window is short: they skip the slow seedling stage and flower sooner, and you can see the colour before you buy.
Set plants out on a mild, overcast day if you can, so they settle without wilting, and water them in well at planting time. Pinch out the growing tip once plants have a few sets of leaves, and repeat pinching through the early growth period to encourage bushy plants and more flowers — then stop pinching well before flowering so buds can form. Set a short support in place early for tall types, because staking later risks damaging the roots.
Soil, spacing, sun and water
Chrysanthemums want full sun and rich, well-drained soil with a pH of 6.0–7.0. Dig in well-rotted compost before planting and space plants 12–18 inches apart, since crowded mums stay damp and invite disease. In Zone 13's heavy rains, drainage matters more than fertility: raise beds slightly or add compost to heavy soil so roots never sit in standing water. Mulch lightly to keep soil moisture even, but keep mulch away from the stems.
Chrysanthemums need moderate water: water deeply and less often rather than lightly every day, water at the base in the morning so leaves dry before night, and check the soil a finger's depth down, watering when it feels dry there. In Zone 13's heat, consistent watering matters more than total volume, and plants in full flower are thirstier than young plants. The watering calculator can help you work out a routine that keeps mums moist without waterlogging them.
Companion planting
Good companions for chrysanthemums include lavender, marigolds, garlic and chives. Lavender and marigolds draw pollinators and beneficial insects to the bed, while garlic and chives are traditional companions said to deter aphids. The companion planting finder can suggest combinations for your whole bed. Chrysanthemums also sit well with asters, which flower over the same cool season, and their strong scent is said to deter some pests from neighbouring plants.
Give mums room and air: their worst problems in Zone 13 come from still, damp air, so do not crowd them with tall neighbours. Put them in the middle of a border, with lower flowers in front and taller plants behind, so air moves freely around them. Avoid planting chrysanthemums where other mums grew last year if disease was a problem, and keep them away from plants that need very dry soil, since mums like steady moisture while they are in flower.
Pests and problems
The common pests and problems to watch for with chrysanthemums are aphids, slugs and thrips. Aphids cluster on shoot tips and buds and can distort new growth, so check the undersides of leaves weekly and wash small colonies off with a strong jet of water. Slugs chew ragged holes in leaves and young shoots, especially in damp weather, so look under pots and mulch in the morning. Thrips rasp the petals and leave silvery streaks on flowers — remove badly marked blooms and keep plants well watered, since stressed plants suffer more.
In Zone 13's year-round warmth, pests never get a winter break, so check plants weekly rather than waiting for damage to show. Good air flow helps: space plants properly, avoid overhead watering late in the day, and remove spent flowers and damaged leaves promptly. Leaf spot and powdery mildew can appear in humid weather — water at the base, mulch, and give plants room to breathe rather than crowding them.
Harvest and storage
Chrysanthemums flower 90–120 days after sowing or planting, and cutting keeps them coming. Deadhead spent flowers every few days, and cut stems for the vase in the cool of the morning, choosing blooms that have just opened. Cut long stems down to a leaf joint, and the plant will branch and produce more flowers. In the heat of the hottest months, flowering slows and then stops, so enjoy the display while it lasts, then cut plants back and let them rest.
For the longest vase life, cut in the morning, strip the lower leaves, and put stems straight into cool water. Chrysanthemums are among the longest-lasting cut flowers, so they are well worth growing for the vase. After flowering ends, cut stems down to near ground level, clear away the debris so disease does not carry over, and mulch over the crown. A plant that survives the hot season may shoot again with the next cool season — watch for new growth in the cooler months and divide crowded clumps then.
Making the most of Zone 13
Zone 13's advantage is time, but chrysanthemums are a cool-season flower: they give you a bright display in the coolest months and then rest through the heat. The trick is to plant for the cool season, pinch for bushy growth, and keep a simple notebook of what you planted and when it flowered — after one season you will have a record far more useful than any general guide. Related reading: asters share the same cool-season flowering habits, and January in Zone 13 is a great month to plant. Marigolds in Zone 13 are a warm-season companion that takes over the bed once mums finish. Related reading: Asters in Zone 13 share the same habits, and January in Zone 13 is a great month to plant. For a planting plan tailored to your postcode, try the planting calendar by zip.
Frequently asked questions
When should I plant chrysanthemums in Zone 13?
Plant chrysanthemums in the coolest months, roughly November to February. Zone 13 is frost-free with winter lows above 60°F, so there is no last frost date to count back from. Check your local extension service — these are zone averages, not exact dates for your garden.
How long do chrysanthemums take to grow in Zone 13?
Seeds germinate in 7–14 days, and plants flower 90–120 days after sowing or planting. In Zone 13, plant in time for the coolest months so flowers arrive before the hot season, since heat shortens the display.
Can I grow chrysanthemums all year in Zone 13?
No — chrysanthemums are a cool-season, short-day flower and fade in Zone 13 heat. Grow them for the cool season from November to February, cut them back after flowering, and let them rest through the hot months; they may return next cool season.
What soil and spacing do chrysanthemums need in Zone 13?
Chrysanthemums need full sun and soil pH 6.0–7.0, spaced 12–18 inches apart. Dig in well-rotted compost, water at the base, mulch lightly, and test your soil through your local extension service.
Should I pinch chrysanthemums in Zone 13?
Yes — pinching young plants encourages bushy growth and far more flowers. Pinch the growing tips through the early growth period, then stop well before flowering so buds can form.