Planning Annual Vegetable Crops
What are Annual Plants?
Annuals plants go from a planted seed to producing a seed within a year. They complete their whole lifecycle in one year or season. Annual plants make up most of our vegetable crops, and many of them can be harvested within 2 to 3 months after sowing. (Bi-annual plants are simliar to annuals but they may live up to two years before producing seeds and coming to the end of their lives.)
Annuals are generally classified as a “warm season” crop or a “cool season” crop.
- Cool season crops thrive in cool areas or during cooler months of the year.
- Generally they are the root, stem, leaf, and flower bud crops.
- in mild winter areas many of these crops can “overwinter” if planted in the fall or can be planted in early spring for a late spring harvest.
- Warm season crops thrive in warm areas or during the hotter months of the year.
- Generally they are the fruit and seed crops.
- They are often planting in the mid-late spring – summer.
Gardeners use planting charts or the information found on seed packets, along with average frost dates, to determine when to plant an annual plant. Both planting charts and seed packets refer to weeks before or after frost dates as a guide of when to sow seeds or plant transplants outdoors.
"Last frost” dates usually land in the late winter or spring. The “first frost” date lands in the fall or early winter. Depending on the type of plant planting charts and seed packets will usually instruct you to sow or transplant before a first frost and to sow or transplant before or after a last frost date.
Contact your local Master Gardener (In CA visit www.mastergardeners.org, your nursery professional, or the following to find out your region's frost dates.
Planning Your Planting Times
Start by finding your average frost dates:
- Victory Seeds lists frost dates for Canada and the U.S.
- LetsGrowVeggies.com lists U.S. frost dates and provides a planting guide based on your frost date.
Learn how to read a seed packet:
Then use information on seed packets or a planing guide like these:
Other useful guides:
- Life Lab's Planting for a School Year Harvest – a simple list of edible crops suitable for mild winter area planting.
- Territorial Seed Winter Planting Date Chart – winter harvest means late summer planting, view their chart Note: in mild winter areas some crops can be planted a couple weeks later than noted in their chart, but don't wait too long, you want your little plants to be establish before day light decreases and temperatures drop.
- Clyde's Vegetable Planting Slide Chart is a handy, easy to use, vegetable gardening slide chart for the home and hobby gardener. This unique Slide Chart presents gardening events in a "time phased" format so that it is possible to see at a glance the entire vegetable planting, growing and harvesting period.
- Organic Gardening.com : Get gardening tips, sign up for monthly garden reports for your area, and simplified information on the care and harvest of garden plants.
- National Gardening Association's Food Garden Guide : Detailed information on planting, care and harvesting of garden plants.
- Burpee.com : Great information on gardening and seed catalog, sign up for regional garden reports, visit their "library" for plant care and harvest information. visit their "nutrition guide" for vegetable nutrient content and garden kitchen tips.
Planning Your School's Edible Harvest
One of the most challenging aspects planning a school garden harvest is that most crops are ready for harvest in the summer months when most schools are out of session. With a bit of planning you can create a crop harvest schedule that fits with your school year.
Here are the three main "windows" for planting and harvesting in a traditional school year calendar:
- Late Spring Harvest – cool season crops planted in late winter-early spring can be harvested before school lets out.
- Fall Harvest – warm season crops planted in late spring (right before school lets out) can be harvested when school starts back up assuming the garden is watered and weeded during the summer.
- Fall/Winter Harvest – cool season crops planted in late summer-early fall can be harvested in the late fall-winter time.
Seed packets and crop information sites list the "days to harvest". The days to harvest are an approximation of how many days it will take for your plant to go from a newly sown seed to an edible treat. Refer to days to harvest to help plan your harvest dates. It is simple as setting the day you'd like to harvest a crop, finding the days to harvest of the particular crop and then counting backwards to determine your sowing date. Of course there are many other variables like the weather, irrigation, fertilization, and pests that may accelerate or retard a plants growth but all of those variables are learning opportunities for the gardener(s).
- Planning and Planting Annual Crops – a PDF summary of the information on this page.
- Edible Theme Garden Calendar – an Excel document created for the Central Coast of California which can be modified for your growing conditions.
- Edible Theme Garden Plans – edible theme seed packet collections.
Planning a Fall Harvest
One mistake many new school gardeners make is planting a garden that matures during summer while students are away. If you are serious about harvesting vegetables in the fall, pick long season vegetable varieties. Read the "days till harvest" listing on the back of seed packages and plan accordingly. If you want to eat fresh corn in September with your students, plant 90-100 day corn in late May instead of 70 day corn. Better yet plant crops that can dry in the garden like popcorn. Popcorn can dry in the field for weeks once mature whereas sweet corn needs to be harvested within a week or two window. Also remember that many vegetables need to be harvested to keep producing throughout the summer so make sure your summer garden guardians harvest regularly to encourage continual fruiting. It is also a good idea to plant later in the spring or in early summer so that the crops will mature later in the summer or early fall when students return to school
Try planting some of these crops in late May or June and come back to school with something to harvest.
Shelling Bean (dry beans)
Edible / Birdseed Sunflowers
Winter Squash or Pumpkins
Health Master Carrots
Try planting a Three Sisters Garden with popcorn, winter squash, and dry beans. Our friends at www.kidsgardening.com have a good article on the Three Sisters Garden.
Check out our tips for school garden summer care.