My Spring Garden Checklist
/The days are getting longer, the snow is melting and the sun is showing up more often – that means it’s almost time to start gardening, right? But hold on, it’s a bit early for us northern growers. I’ll walk you through a typical spring as I get ready for another season of flower farming here in northwest Montana, zone 5b.
If you read My Fall Cleanup Checklist, this is the spring version. I probably won’t remember everything I typically do in the spring, but it will be a good overview. And after 10 years of growing cut flowers, I’ve definitely relaxed about my spring schedule. I used to try to plant as early as possible, creating row covers with frost cloth that would inevitably be flattened with wet snow in early May. I tried planting ranunculus in the high tunnel in fall for an early crop, but the results weren’t worth the effort. I’ve learned that spring always takes its time, and I get better results – and healthier plants – when I don’t try to rush things.
March
This month brings dramatic changes in weather, day length, temperatures and precipitation. It might be warm and dry one day, then windy and damp the next. Even if the snow is gone and some green shoots are starting to pop out of the ground, it’s too early to do much work outside. Many insects are still overwintering in the soil and leaves, so don’t disturb them yet.
Spring snow is an important source of moisture for our gardens. We often have snow storms until early May.
Most of my work in March is still indoors, and it’s also when seed starting really kicks off. I have a setup in the basement with tables, lights and heat mats. Over the course of a few months, I’ll grow hundreds of plants that will be transplanted outside, mostly in May.
In March some of the main tasks are:
Finish my garden plan (I use the Garden Planner by GrowVeg.com).
Start seeds, following the schedule I’ve created in Airtable. In March I start lots of stock, snapdragons and other hardy annuals (plants that like cool temperatures and get planted outside in late spring).
Record germination counts so I can adjust my garden plan as needed. I always start extra seeds, especially for varieties with low germination rates. Because my flower farm is small, I plan carefully so I can fill all the available growing space.
Start prepping the high tunnel for planting, which means cleaning up any annuals that were left over the winter, pulling weeds, and adding compost and mulch.
April
It’s time to start working outside, although the weather is often variable. I often plan my weeks around the weather to take advantage of warm, dry days for outdoor work.
Common tasks for the month of April:
Continue starting seeds and recording germination rates, as well as tending seedlings daily. Timers control the lights and a fan, but I water and fertilize based on moisture levels and growth rates. I use a mild organic fertilizer a couple times a week on most seedlings.
Walk around and see what’s starting to pop up outside. This is one of my favorite things to do in spring. I love seeing the green shoots emerge, as many perennials start to send up new leaves. Snowdrops and other tiny bulbs are the first to bloom, and every week there’s something new coming up. But still, I leave the leaves and mulch on all the plants – they’ll come up just fine through it.
Pull weeds wherever they’ve popped up, being sure to smooth the soil and cover it with leaves or mulch. Many of our common weeds are perennials, meaning they can continue to grow slowly through the winter. Many of them have deep taproots. It’s best to pull these early in the spring when the soil is soft and before they start to flower or produce seeds.
Direct seed the hardiest flowers like nigella, larkspur, poppies and bupleurum, along with vegetables like carrots, radishes, spinach and snap peas. When direct seeding I disturb the soil minimally, and I’ll often add a layer of compost or fine mulch to cover the soil, especially if the seeds need darkness to germinate.
Plant the first round of ranunculus corms. I soak them for several hours and then plant directly in the ground – no presprouting. I’ve found it works well in my climate, and this way it doesn’t take up room indoors.
Start hardening off seedlings in mid April to prepare them for transplanting. Sometimes this coincides with snow on the ground (see photo below). During the hardening off process, I’ll set out trays on the porch as soon as it’s above 40 or 50 in the morning, and bring them back inside in the evening. Each plant needs about a week of hardening off before transplanting. This means many trips up and down the basement stairs every day for weeks – but it’s worth it because the plants are gradually adapted to outdoor conditions and have an easier time at transplanting.
Add mulch and compost as needed. It helps to add nutrients and organic matter and also keeps the soil covered so it doesn’t dry out as quickly. Our clay soil can crack and split when it’s dry, so it’s best to avoid that.
Hand water the direct seeded areas and early transplants. We typically don’t get much rain in April and it’s too cold to turn on the irrigation, so for a while hand watering is a daily task.
May
Ahh, May. This is one of my favorite months. Everything is greening up, the days are warmer and more plants start blooming. There is lots to do in the garden.
While plants are rapidly putting on growth, the nights are still cool and frost is possible. I usually wait to plant tender crops (zinnias, marigolds, celosia, tomatoes, etc.) until the second half of the month.
In May the garlic and other fall-planted crops grow tall, while much of the garden looks sparse until the transplanted annuals fill in.
Tasks for May:
Do a thorough inventory of perennials in the garden – see what’s growing, what might have died over the winter and where I have gaps to fill.
Transplant seedlings and plant the second round of ranunculus corms, as well as gladiolus bulbs and dahlia tubers.
Continue direct seeding, and start seeding cover crops as well. I use direct seeded varieties like sunflowers, and certain cover crops like phacelia, to fill in gaps.
Turn on the irrigation and check for leaks.
Continue weeding.
Start thinning crops that were direct seeded in the fall if they’re coming in too thick.
Set up the rain barrel.
Cut back perennials that were left standing over the winter. In mid May it’s usually warm enough to do cleanup like this without worrying about disturbing any insects that might be nesting in stems, although I often leave the stems where they fall as an extra source of mulch.
Start regular applications of compost tea with molasses to transplants and some perennials, especially those prone to insect damage. Boosting the soil health means healthier plants, and increasing the sugars in the plant tissues can help deter some insects.
Add shade cloth to the high tunnel once the daytime temps are consistently near 80.
Start working the compost piles left from last fall. This can be started earlier in the spring, but by May it’s a bit warmer and I’m spending lots of time outside, so it’s a great time to turn the compost piles, adjust the ratio of greens and browns, and wet the piles if needed.
Bring flowers inside to enjoy! I don’t usually book events in May since the blooms are sporadic, and I like to leave lots of flowers for the early pollinators to enjoy. But some blooms, especially lilacs, just have to be brought inside to enjoy their brief and fragrant beauty.
Are you excited for spring now? I know I am. But I’ll try to keep my patience as the weeks go by, with our part of the world gradually warming up and greening up. The rewards of spring will be worth the wait.