How often to water Black Tower elderberry in California
In July in the Central Valley, established Black Tower elderberry in loam needs a deep watering about every 20 days: about 8.8 gallons each time for a plant 4 feet across, about 3.0 gallons a week. Black Tower elderberry is a columnar deciduous shrub bred for its narrow form and dark foliage. Leaves emerge green in spring and age to a deep purple-black through the season. It drops its leaves for winter dormancy and leafs out again once the weather warms.
How often to water Black Tower elderberry, month by month
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.
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 the plant covers, and skip a watering after a good soaking rain.
How to tell it needs water
- Soil dry several inches down while new leaves are still pale green in spring signals that it needs water
- Leaf edges curling or crisping during a summer heat spell can indicate the root zone has dried out
- Flat clusters of white flowers wilting quickly in hot weather warrant a soil check beneath the mulch
- Leaves yellowing and dropping early while the soil underneath stays wet can indicate overwatering or poor drainage
- Stems that stay soft or blacken at the base after wet weather warrant a look at drainage before more water
How to water it
- Water Black Tower elderberry over the whole root area beneath and just around the canopy
- Soak the ground to a good depth, then let the top few inches dry before the next watering
- Use drip emitters on soil that drains well, building a raised bed where clay holds water
- Keep a layer of mulch over the roots, pulled back from the woody stems at the base
- Widen the watered area gradually as the shrub fills out toward its mature spread
Through the seasons
A newly planted Black Tower elderberry needs regular soil checks through its first summer while roots settle in. Established plants still prefer even moisture through the growing season, tapering off once leaves drop for winter dormancy. On the north-central coast, WUCOLS rates it moderate water, with cooler season rain helping cover part of that need. In the Central Valley, it rates low water, where established plants lean on periodic deep soakings instead. WUCOLS has not evaluated it for the south coast, South Inland, the high desert or the low desert, so treat a planting there as unproven and watch the soil closely.
In pots
A potted Black Tower elderberry needs a container large enough for its woody stems to anchor firmly. Check the mix two inches down in summer heat and water once it feels dry, letting excess drain fully before emptying the saucer. Its columnar form suits a large pot on a patio, though growth stays best with room for roots to spread. Once the plant drops its leaves for winter, water far less often and keep the pot away from standing water or ice.
- A year
- 6.84 gal per sq ft
- Reference
- Sacramento climate table
- Counts
- Plant need, before sprinkler losses
Monthly water need by climate zone
Black Tower Elderberry: gallons per square foot per month, by WUCOLS climate zone
| Month | N. Coast | C. Valley | S. Coast | S. Inland | Hi Desert | Lo Desert |
|---|---|---|---|---|---|---|
| Jan | 0.37 | 0.16 | – | – | – | – |
| Feb | 0.53 | 0.26 | – | – | – | – |
| Mar | 0.87 | 0.43 | – | – | – | – |
| Apr | 1.18 | 0.61 | – | – | – | – |
| May | 1.46 | 0.83 | – | – | – | – |
| Jun | 1.61 | 0.99 | – | – | – | – |
| Jul | 1.61 | 1.07 | – | – | – | – |
| Aug | 1.49 | 0.95 | – | – | – | – |
| Sep | 1.24 | 0.72 | – | – | – | – |
| Oct | 0.87 | 0.47 | – | – | – | – |
| Nov | 0.47 | 0.22 | – | – | – | – |
| Dec | 0.31 | 0.14 | – | – | – | – |
| Year | 12 | 6.84 | – | – | – | – |
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 low water in the Central Valley, like Black Tower elderberry. Plants that drink alike can share one valve and one schedule.
LavenderLavandula spp. & cvs.low water, Central Valley1.07 gal/sq ft in July
RosemaryRosmarinus officinalislow water, Central Valley1.07 gal/sq ft in July
BougainvilleaBougainvillea & spp. & cvs.low water, Central Valley1.07 gal/sq ft in July
Olive TreesOlea europaea ssp. & cvs.low water, Central Valley1.07 gal/sq ft in July
Crape MyrtleLagerstroemia spp., hybrids & cvs.low water, Central Valley1.07 gal/sq ft in July
LantanaLantana camara ssp. & cvs.low water, Central Valley1.07 gal/sq ft in July
SalviaSalvia greggii ssp., cvs. & hybridslow water, Central Valley1.07 gal/sq ft in July
AloeAloe spp. & cvs.low water, Central Valley1.07 gal/sq ft in July
SucculentsEcheveria spp. & cvs.low water, Central Valley1.07 gal/sq ft in July
JunipersJuniperus spp. & cvs.low water, Central Valley1.07 gal/sq ft in July
Russian SagePerovskia spp. & cvs.low water, Central Valley1.07 gal/sq ft in July
SagebrushArtemisia spp. (shrubby)low water, Central Valley1.07 gal/sq ft in July
Wild PrivetLigustrum vulgarelow water, Central Valley1.07 gal/sq ft in July
CoralberrySymphoricarpos orbiculatus (SHADE)low water, Central Valley1.07 gal/sq ft in July
Sydney Golden WattleAcacia longifolialow water, Central Valley1.07 gal/sq ft in July
Blue Leaf WattleAcacia salignalow water, Central Valley1.07 gal/sq ft in JulyTurn this into minutes on your water days
Every city page has a calculator that takes Black Tower elderberry, 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 Black Tower elderberry need per day?
In July in the Central Valley, established Black Tower elderberry needs about 0.4 gallons a day for a plant 4 feet across and about 1.7 gallons a day for a plant 8 feet across. Give it in deep waterings spread days apart rather than a little every day, so the whole root zone gets wet.
Does watering for Black Tower elderberry change across California?
Yes. WUCOLS rates Black Tower elderberry separately for each of the six California climate zones: moderate water in the North-Central Coastal zone, low water in the Central Valley zone, not evaluated in the South Coastal zone, not evaluated in the South Inland zone, not evaluated in the High and Intermediate Desert zone, not evaluated in the Low Desert zone. The monthly table above shows how the same rating translates into different gallon amounts as reference evapotranspiration changes.
Why did my Black Tower elderberry lose its leaves in fall?
This shrub is deciduous and drops its leaves as part of a normal winter rest. New growth returns once temperatures warm in spring. Reduce watering while the plant stands bare.
Should I prune Black Tower elderberry before or after watering season?
Prune it once it is dormant and bare, typically in winter. Cutting back old wood then encourages the strong new growth that carries next season's dark foliage. Avoid heavy pruning during active summer growth.
Why are my elderberry leaves turning green instead of staying dark?
New leaves emerge green and darken as they mature. A mix of green and dark foliage during active growth is normal.
Does Black Tower elderberry need staking?
Its columnar form is naturally upright, but a young plant in a windy or exposed spot may need a stake. Remove the stake once the woody stems can support the canopy alone. This is separate from any watering routine.
Can I grow Black Tower elderberry in a hot inland yard?
It has only been planted with confidence on the coast and in the Central Valley among the ratings here. In a hotter or drier region, watch a new planting closely and adjust based on how the soil and foliage respond.
Is Black Tower elderberry fruit worth harvesting?
Some fruit can follow the flowers later in summer, though this selection is grown mainly for its foliage and form. If berries appear, they follow the same care as the rest of the shrub. Do not rely on watering changes to boost fruiting.
More plant watering guides
Sources
- WUCOLS IV plant water use classification for Sambucus nigra 'Eiffel 1', the University of California survey California agencies use for landscape plan reviewRead August 23, 2026 on wucols.ucdavis.edu
- Model Water Efficient Landscape Ordinance, adopted text and appendices, effective 2025-01-02 · monthly reference evapotranspiration per city, Appendix CRead August 23, 2026 on water.ca.gov/-/media/DWR-Website/Web-Pages/Programs/Water-Use-And-Efficiency/MWELO-Rulemaking/Final-MWELO-Text-and-Appendices_20250103.pdf
- UC Statewide IPM Program, irrigation scheduling using evapotranspirationRead September 30, 2026 on ipm.ucanr.edu/PMG/GARDEN/ENVIRON/evap.html
- Shaw and Pittenger, Landscape Irrigation System Evaluation and Management, UC Cooperative Extension, 2009Read September 30, 2026 on ucanr.edu/sites/default/files/2013-02/160836.pdf
- Pittenger, Water Management in Gardens and Landscapes, UC Riverside, 2017Read September 30, 2026 on ucanr.edu/sites/default/files/2017-03/258022.pdf