What the heck is a planting zone?

What the heck is a planting zone?

How do I find my planting zone?

Why does zone matter?

How do I know what kind of plant I’m planting?

What if I’m a rebel and I wanna plant stuff that isn’t for my zone?

Vocabulary for the day 

Hardiness Zone, Frost-Cloth, Annual, Tender Annual, Perrennial, Half-Hardy, Semi-Annual and Biennial 

Your “zone” refers to the USDA Plant Hardiness Zone Map. It breaks down geographic locations in the US according to the average minimum temperature. Basically how cold does your area get. Based on the average weather data collected from stations all over the country. Zones are coldest to hottest 1-11 divided by 10degree increments. Zones can be subdivided into 5 degree subcategories like zone 8a and 8b. Zone 1 is central and North Alaska and coldest temperatures expected in winter can be -50 while zone 11 in Hawaii doesn’t get any colder than 40-50, Lucky Ducks. 

Most of us don’t deal with those extremes and land somewhere in the middle. https://planthardiness.ars.usda.gov The USDA has an interactive map that will tell you your zone based on your zip code. It’s a little clunky but helpful if you don’t know a zip code. We garden in zone 7a 

Why it matters? Hardiness zone is important to consider when planting anything that stays in the ground for 9 months or more. Plants can only survive above a certain temperature. And they are all different. 

I want to plant stuff How do I know?

Check your plant tag or seed packet there will be terms like:

Treated as annual; Some plants are perennial “treated as annuals” when grown outside their hardiness zone. Many are short lived perennials but so Hi-Mai (or rough looking) to keep alive all year it’s not worth it like pansies, tulips or ranunculus. * see should I save the bulb

For your zone is your seed/plant?

Annual; also called Tender Annual;

This is a plant that begins from a seed planted every year. After its bloom cycle it goes kaput. You will need to plant fresh every year. Larkspur, Nigella, sunflowers( Some annuals will self seed and new babies will show up the next year. *see our favorite self-seeders*) 

Half-Hardy, Tender Hardy, Semi-Hardy;(insert dirty joke) this is a Hardy plant that can withstand cool temperatures but is sensitive to freezing and frost. Often a short lived perennial. Many fall and early spring blooms fall in this category. Chrysanthemums

Biennial; are a pain in the bum.

Yeah, they are worth it but…annoying. Biennial plants have a 2 year growth cycle before blooming and many need a cold period to bloom. They typically grow as greenery only for a season, die back in winter and will return and grow the following season. Foxglove and Sweet William if planted in early fall will bloom late spring the following year. 

Short lived perennial; is more sensitive to temperature swings of hot and cold. They will return 3-5 seasons if happy. Delphiniums, slow to grow and start will beef up the next few years and then die back. Pansies(zone 7-10) are a short lived perennial. When fall planted a happy pansy can survive down to 20°and will rebound in spring. Pansies struggle in summer heat and can look rough. Many pull them out to plant fresh in fall; treating them as an annual.

Perennial; a true perennial has a long life and will return season after season. A happy Peony will last 100 years! 

This is confusing! These terms are fluid. Lots of our favorites are considered annual and perennial depending on where you grow. In general the longer something will live the slower it is to get established. A peony May not flower for the first two years. Whereas a sunflower seed planted May 15 can be 6ft tall by July and a withered stick by August. 

TBH temperature is a big black hole! Without getting wrapped around the axle about climate change (Feel free to scream in a paper bag now) 

ToBeClear; Seed Germination temperature, Transplant Temperature, Soil Temperature. Optimum Growing temperature, Sun Light, Day length. 

Black Hole. You got this.

One at a time

Back to Hardiness Zone-

A Cautionary Tale

So, I planted a lemon tree. I wanted lemons for my cocktails. The little lemon tree I planted was Hardy to zone 8(10-20°) I’m in zone 7. I bundled up the tree and crossed my fingers. There has to be an upside to climate change, right? This winter we had no snow and it was unbelievable mild. But 5 sneaky days in a row in December we got to 15°. RIP lemon tree.  

Hardiness zone is always painting with a broad brush. 

Remember when I said plants have max low temperature they can survive at and they are all different? 

Meyer Lemon Tree’s low temp is 20° and while technically that is zone 8 multiple days of 15° were too much. 

So what’s the point?

1. Hardiness is only a consideration for something you want to live through the winter! In colder zones many things are successful treated as an annual
2. If you plant well within your zone. No worries. You do NOT need to look up every single temperature. Peonies are  hardy zone 3-8. I’m in zone 7. I pay no attention to my peonies in the winter. Kale is Hardy to zone 7. So I look up “lacinto kale cold temperature tolerance” it’s fine down to 10° so I ignore it all winter. Unless we have a really cold snap below 10°
3. But I’m wild and dangerous and I like waking up in the middle of the to check the weather app on my phone. And y’know, Ranunculus! *see all things ranunculus. If you are overwintering plants and live on the edge of their hardiness zone always have frost cloth on hand. Always. Enough to cover your plants. If fact you can leave them covered all season. Plant Vulnerable plants together in a place that’s easy to get to. It is much easier to cover a 4’x8’ bed full of ranunculus then polka dot tents throughout the yard
4. What is frost cloth? Also called Frost Blanket or Row covers. It’s exactly what it sounds like. A piece of fabric that can protect your plant from low temperatures. It is semi-permeable and allows sun and some water in. There are many brands be sure to check how much protection your cloth gives. Frost cloth will NOT guarantee your plant survives a hard freeze. It will only provide up to 8° of protection. All the frost cloth in the world won’t let me grow a pineapple m. We use Agribon AG-19 2-4° protection, AG-30 4-6°, AG-50 6-8° AG-70 8°+. Heavier protection will let in much less light and water, be mindful and check on plants often with longterm use heavy cloth. Winter water tip, zone 8-3 many plants in winter are growing slow. Their need for water will be reduced. Root Rot is a high risk at this time. We do not water our covered plants December-February but every garden is different. 

We hope this helps. Don’t get overwhelmed! Remember if your plant dies it isn’t murder. You’re learning. You can always plant another. 

Cheers!

HHF