It’s Spring Planting Season

By | March 10, 2021

We all want a beautiful, flourishing, healthy landscape.  Before you go and spend a bunch of money at the garden center, here are a few things to consider so you won’t waste your time and money.

USDA hardiness zone map

Make sure the plant is for our zone. Pinellas County has two USDA hardiness zones.  Safety Harbor and north is 9b; south of Safety Harbor is 10a.  Since plants respond differently to temperatures, it is important to choose plants that can tolerate your winter temperatures and your summer heat.  Hostas are a favorite for northern gardeners, but here they wither away and die during summer heat.  Tropical plants are also a favorite for their landscape effect, but we are not in a tropical zone.  Tropical plants can be killed by a cold winter.  It is best to know a plant’s hardiness zone before heading to the garden center.  Only purchase plants that fit your zone.

Know if your soil is moist, wet or dry.  Your soil moisture can vary greatly.  Some soils are very well-drained and don’t hold water.  Drought-tolerant plants are best suited for very dry soil (i.e., Blanket flower (Gaillardia pulchella), Turkey oak (Quercus laevis), red cedar (Juniperus virginiana),  Florida privet (Forestiera segregate), yaupon holly (Ilex vomitoria), muhly grass (Muhlenergia capillaris), coontie (Zamia integrifolia), blue porterweed (Stachytarpheta jamaicensis), wild lantana (Lantana involucrata).  Some soils are seasonally very wet (during the summer).  Look for plants that can tolerate wet roots or extended flooding for the summer months (i.e., False-indigo bush (Amorpha fruticose), saw palmetto (Serenoa repens), elderberry (Sambucus nigra subsp. Canadensis), shiny-leaf wild-coffee (Psychotria nervosa), gallberry (Ilex glabra), Walter’s viburnum (Viburnum obovatum), firebush (Hamelia patens), wax-myrtle (Morella cerifera).

This shows nutrient availability of several elements at different pH

Nutrient availability by soil pH

Determine your soil’s pH.  Many of our coastal soils are alkaline.  If you have sea shells, marl or limestone in your soil then you can be sure it’s alkaline (pH above 7).  The soil around new masonry buildings can also be alkaline from the concrete.  A soil with a high pH (alkaline soil) can cause a lack of nutrients for several plants.  Gardenia, ixora, azalea, blueberry, bahia grass, phlox and American holly prefer an acidic soil.  When these are planted in an alkaline soil, they will show a lack of nutrients that cannot be cured by adding fertilizer to the soil.  Know your soil pH and choose plants accordingly.  You can send a soil sample to the University of Florida using this form:  http://edis.ifas.ufl.edu/pdffiles/SS/SS18700.pdf

This is a picture of a landscape showing plants chosen for their mature size to fit in the planting area.

Choose plants for their mature size

Choose plants for their mature size.  A common pitfall is to choose large, fast-growing plants.  These give an immediate result, but require much more maintenance to keep them trimmed and in-bounds.  Choose plants that will only get as large as the area where they are planted.  If a four-foot hedge is needed, choose a plant that only gets four feet tall.

 Install plants next to structures at a distance that is half the plant’s mature width plus one foot.  Example:  A plant that is five feet wide at maturity should be planted three and a half feet from the wall (1/2 of the total mature width of the plant plus 1 foot).  This spacing will help insulate the house from hot and cold air, allows for termite inspection, house repairs or painting.  In addition, when plants touch the house ants and roaches have a bridge into the house over the insect spray around the building.

Cherokee bean

Choose Florida Native Plants.  Native plants have evolved here for millions of years and they are adapted to our weather extremes.  They have also developed with the wildlife and provide food when it is needed.  Properly placed native plants  will use fewer resources to thrive and they help  restore Florida’s environment and wildlife.  Exotic species can become invasive and are very harmful to Florida.  Many are still sold by the nursery industry.  It is safer and better for the environment to use native plants.  There are 567 Florida native plants headed for extinction, so help them out.

Proper planting

Planting.  When planting, be sure to dig the hole 1.5 times the width of the root ball.  If the soil is hard or compacted, the wider the hole the better.  Dig the hole just deep enough so that the top of the root ball is 10% above grade.  Apply mulch up to the root ball, but leave the top of the root ball bare of mulch or only slightly mulched.  This will allow water to easily reach the root ball and thoroughly wet the root system.   If roots are growing in a circle cut the root just before it turns to circle.  For more information see:  http://edis.ifas.ufl.edu/ep112. This publication will provide information on planting, fertilizing, mulching, staking, establishing and irrigating.

For more information or help with selecting plants, visit your local University of Florida/IFS office.