WateringTimesWatering plan, $19
Magnolia champaca (Michelia champaca), WUCOLS IV

How often to water champaca in California

In July on the north-central coast, established champaca in loam needs a deep watering about every 13 days: about 55 gallons each time under a 10 foot canopy, about 29 gallons a week. Champaca, listed by WUCOLS as fragrant Himalayan champaca, is an evergreen tree in the magnolia family with glossy, slightly drooping leaves. Its orange to golden yellow flowers are so fragrant that their oil goes into perfume. It is frost tender, likes soil that is moist but well drained, and resents having its roots disturbed.

TreeRated for 2 of 6 zones

How often to water champaca, month by month

Your city
Canopy width
10 ft
Your soil

Type your city above and the days between waterings and the gallons appear here, worked out from your city's climate table. Or read the figures by climate zone further down.

Every month, on your water days. The personal plan prints this for champaca and the rest of your yard, on the days your water supplier allows.Get the plan for $19

How this is worked out: established roots fill the top 1.5 feet of soil, and you water again when that soil has dried halfway. Loam soil holds about 1.5 inches of water per foot. Water the whole area under the branches, and skip a watering after a good soaking rain.

Which soil do you have?

Dig down a few inches, take a handful of moist soil and squeeze it.

  • Sandy: gritty, falls apart when you open your hand, will not form a ball.
  • Loam: forms a soft ball that crumbles when you poke it.
  • Clay: forms a firm, sticky ball and squeezes out into a ribbon between thumb and finger.

Still not sure? Pick loam. Most garden beds sit between sand and clay.

How to measure canopy width

A tree with its canopy width marked across the widest branches and the circle under it shaded blue

Measure across the branches, from the tips of the outer leaves on one side to the tips on the other. A tape works, or pace it out.

Water the whole circle under the branches, shown in blue. The gallons here cover that circle.

A wider canopy means more gallons each watering, not more waterings. While the tree is young, measure again each spring.

How to tell it needs water

  • Soil dry 2 to 3 inches down at the edge of the root ball means champaca needs a deep soak
  • Leaves that lose their gloss and curl during a hot, dry spell point to a thirsty tree
  • Yellowing leaves and dieback over soggy soil warrant a check for Phytophthora root rot
  • Gray fuzzy mold on buds and flowers in damp, still weather is gray mold, so keep spray off the canopy
  • Leaves blackened after a cold night show frost damage rather than a need for water

How to water it

  • Water slowly over the root ball and the soil around it, using drip or a soaker ring
  • Wet the soil about 18 inches deep, then let the top couple of inches dry before the next soak
  • Plant in loam, clay or sand that stays moist but drains, and raise the bed where water stands
  • Mulch the root zone to hold moisture, keeping the mulch off the trunk
  • Choose its final spot at planting and avoid digging around it later, since it resents root disturbance

Through the seasons

Keep a new champaca evenly moist through its first summers while the roots spread, then water deeply whenever the topsoil dries. This evergreen holds its leaves all year, so it still uses some water in winter, though far less than in summer. A tree raised from seed may need a decade before its first flowers. Coastal winter rain usually covers the cool months. On the south coast and the north-central coast, WUCOLS rates champaca moderate water. WUCOLS has not evaluated it for the Central Valley or South Inland. The low desert and the high desert are marked as not suited.

In pots

Champaca is often grown in a large container, so it can be wheeled under cover before frost. Check the mix 2 inches down every couple of days in summer, and water when it is dry there. Soak until water drains out the bottom, then empty the saucer, since soggy mix invites root rot. Repot rarely and gently, because the roots dislike being disturbed. In winter, water less as growth slows, and keep the pot where it will not freeze.

1 Your climate zone six WUCOLS zones, each from its own reference city
Not ratedWUCOLS does not rate Champaca for the Central Valley zone
A year
no figure
Reference
Sacramento climate table
Counts
Plant need, before sprinkler losses

WUCOLS lists Champaca as not evaluated for the Central Valley zone, so no monthly figure is computed here.

Monthly water need by climate zone

Champaca: gallons per square foot per month, by WUCOLS climate zone

MonthN. CoastC. ValleyS. CoastS. InlandHi DesertLo Desert
Jan0.37–0.78–––
Feb0.53–0.81–––
Mar0.87–1.15–––
Apr1.18–1.4–––
May1.46–1.61–––
Jun1.61–1.74–––
Jul1.61–1.98–––
Aug1.49–1.86–––
Sep1.24–1.49–––
Oct0.87–1.15–––
Nov0.47–0.84–––
Dec0.31–0.65–––
Year12–15.5–––

How this is worked out: the WUCOLS water rating for each zone times that zone’s climate for the month. A dash means WUCOLS does not rate the plant there. The figures are what the plant uses, before sprinkler losses.

Plants with the same water needs 16

Rated not evaluated in the Central Valley, like champaca. Plants that drink alike can share one valve and one schedule.

Hawthorn MapleAcer crataegifoliumnot rated, Central Valleyno Central Valley ratingMountain MapleAcer glabrumnot rated, Central Valleyno Central Valley ratingMiyabe MapleAcer miyabeinot rated, Central Valleyno Central Valley ratingEverglades PalmAcoelorraphe wrightiinot rated, Central Valleyno Central Valley ratingPink CedarAcrocarpus fraxinifoliusnot rated, Central Valleyno Central Valley ratingYellowwoodAfrocarpus falcatus (Podocarpus falcatus)not rated, Central Valleyno Central Valley ratingNew Caledonian PineAraucaria columnaris (A. cookii)not rated, Central Valleyno Central Valley ratingFormosa Sugar PalmArenga englerinot rated, Central Valleyno Central Valley ratingNeemAzadirachta indicanot rated, Central Valleyno Central Valley ratingBismarck PalmBismarckia nobilisnot rated, Central Valleyno Central Valley ratingAmerican HornbeamCarpinus caroliniananot rated, Central Valleyno Central Valley ratingJapanese HornbeamCarpinus japonicanot rated, Central Valleyno Central Valley ratingAmerican YellowwoodCladrastis kentukeanot rated, Central Valleyno Central Valley ratingPagoda DogwoodCornus alternifolianot rated, Central Valleyno Central Valley ratingGiant DogwoodCornus controversanot rated, Central Valleyno Central Valley ratingButterfly PalmDypsis lutescens (Areca)not rated, Central Valleyno Central Valley rating
Minutes for your sprinklers

Turn this into minutes on your water days

Every city page has a calculator that takes champaca, your sprinkler type and the month, and gives the minutes per water day for that supplier's schedule. Or put it in a zone of the personal watering plan and get all twelve months printed.

Questions people ask

How much water does champaca need per day?

In July on the north-central coast, established champaca needs about 4.1 gallons a day under a 10 foot canopy and about 16 gallons a day under a 20 foot canopy. Give it in deep waterings spread days apart rather than a little every day, so the whole root zone gets wet.

Does watering for champaca change across California?

Yes. WUCOLS rates champaca separately for each of the six California climate zones: moderate water in the North-Central Coastal zone, not evaluated in the Central Valley zone, moderate water in the South Coastal zone, not evaluated in the South Inland zone, not suited to this region in the High and Intermediate Desert zone, not suited to this region in the Low Desert zone. The monthly table above shows how the same rating translates into different gallon amounts as reference evapotranspiration changes.

Can champaca survive frost?

It is cold sensitive and does not survive being frozen. In frost-prone gardens, grow it in a pot and move it under cover for winter. A frost-free coastal garden suits it best.

Why is my champaca not flowering?

Age is the usual reason. Seed-grown trees can take up to ten years to flower, and plants from cuttings may still wait a year or two. Keep it in sun or part shade and steadily watered while you wait.

Is champaca a magnolia?

Yes. It was long classed as Michelia champaca and now sits in the magnolia genus. Its flowers are prized for their scent, and their oil is used in perfume in Asia.

Can I move a champaca tree?

Avoid it if you can, since champaca resents root disturbance. If you must move it, take as large a root ball as possible. Keep that root ball moist until new growth appears.

Does champaca need full sun?

It grows in full sun or part shade. In a hot, bright spot, part shade helps the soil hold moisture longer between soakings.

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Sources