Seasonal Topics

Spring

Take a Self-Guided Spring Plant Walk around the campus!

Spring is probably the busiest time for the Grounds Services Department. Many plants bloom and put on new growth at this time, and insects become active as the weather warms. Frost is no longer a problem, and precipitation comes in the form of showers alternating with sunny skies.

In March, the tussock moth caterpillars hatch and begin eating the foliage and golden tassels of the oak trees on campus. You may see Grounds staff monitoring these pests on a weekly basis. They may also be looking for curling new growth, which might signal an aphid infestation, be it on Spirea or Vinca or cherry leaves.

The soil in the raised beds of the Oval is tested and amended before planting each April. We change the planting pattern from year to year.

Actively growing plants need access to nutrients. We fertilize the turf campus-wide at this time, to supplement the recycled nutrients available from lawn clippings left in place after mowing. The Camellias, Rhododendrons and Azaleas are fertilized after flowering as well.

The Arboretum is flail-mowed from March through September, to reduce the fire hazard of tall grasses. The pruning crew keeps new growth in check, particularly as the campus prepares for Commencement. Groundcovers and shrubs are trimmed around Frost Amphitheater, in White Plaza and throughout SEQ in May.

Campus Blooms

Spring is the peak bloom season for many plants native to California. Planted on campus are western redbud (Cercis occidentalis), flannelbush (Fremontodendron cultivars), Douglas iris (Iris douglasiana) and many selections of wild lilac (Ceanothus cultivars). Naturally occuring are the California buckeyes (Aesculus californica) in the Museum Way fields and along Junipero Serra Boulevard.

Visit the recently renovated New Guinea Garden, at the corner of Lomita Drive and Santa Teresa Streets. New plants to the garden include Kaffir lily (Clivia miniata), Cordyline australis 'Red Star', Canna 'Transvaal Beauty', and Bougainvillea 'La Jolla'.

A sure sign that spring is here is the bloom of flowering crabapples (Malus 'Robinson') at Littlefield Center in late March.

A walk through the Amy Blue Garden delights both the eyes and the nose with flowering cherries (Prunus yedoensis), fragrant rhododendron 'Countess of Haddington', and sweet wisteria.

In Vidalakis courtyard at Schwab Residential Learning Center, the flowering pear (Pyrus calleryana 'Chanticleer') orchard forms a sea of white petals.

In April, the Chinese fringe trees (Chionanthus retusus) in the Thomas Church courtyard at the southwest corner of the Main Quad come into full bloom, as does the India hawthorn (Rhaphiolepis indica) all over campus. The latter, a drought-tolerant flowering shrub forms the low perimeter of the Oval lawn.

In May, spectacular wildflower plantings reach their peak along Campus Drive.

For more information on campus blooms, go to "Plants of Stanford" from the "Horticultural Topics" page.

Month by Month in Your Garden

March:

• Graft fruit trees as buds begin to swell on rootstock.
• Buy camellias, rhododendrons and azaleas in bloom.
• Fertilize with a balanced fertilizer to encourage spring growth. Give high-nitrogen fertilizer to lawns, annual flowers, vegetables, berries, citrus, and fuchsias. Give acid fertilizer to azaleas, rhododendrons, camellias.
• Pull weeds.
• Monitor plants for pests such as aphids, thrips, lacebugs, and beneficials such as spiders, ladybugs and lacewings. Hose off high concentrations of pests with blasts of water.
• Handpick snails and slugs.
• Check that irrigation systems can function properly. Adjust sprayheads, flush out drip lines and check for missing emitters.

April:

• Plant seeds of nasturtiums, sunflowers, and hollyhocks.
• Test and amend soil in areas to be planted with summer annuals. Plant colorful favorites such as begonias, impatiens and pelargoniums (zonal and ivy geraniums.)
• Plant summer flowers: ageratum, cosmos, impatiens, lobelia, marigold, petunia, phlox, portulaca, statice, sweet alyssum, verbena, and zinnia.
• Transplant tomatoes, cucumbers and bell peppers mid-month. Sow seeds of beans, corn, root crops (beets, carrots, radishes, turnips), and greens (lettuce, mustard, chard, spinach). Plant citrus, avocado, subtropical shrubs. Favorites include kumquats, Meyer lemons, Meyer lemons, Mexicola avacado, hibiscus and lantana.
• Feed roses.
• Handpick snails and slugs.
• Monitor apple and pear trees for codling moth.
• Begin watering plants as rains taper off. The ET rate steadily increases from February to June, and plants in May often die from underwatering.

May:

• Harvest cherries and loquats.
• Cut back spring-blooming shrubs and trees after flowering: flowering quince, deciduous magnolias, etc.
• Pinch azaleas, fuchsias, and marguerites for bushier plants.
• Build watering basins for trees, shrubs, and vines.
• Thin fruit and almond trees to reduce brown rot.
• Fertilize azalea, camellia, citrus and gardenia with iron chelate if foliage is yellow with green veins.
• Aerate lawns.
• At the end of the month, apply a 2-3 inch layer of mulch to help retain soil moisture and keep down weeds.
• Remove fire hazards such as brush and debris, and mow dry grasses. Prune out dead branches and keep limbs from within 15 feet of structures. Keep the roof clean and clean out gutters.