Sprout Your Summer Veggie Seeds Now

Gardener’s Notebook by Joshua Burman Thayer

DON’T WAIT! Sow your summer seeds now to ensure they are ready for your garden, come April and May.

Coco Coir is Cash:  When sprouting seeds, an inert non-soil medium is best. My favorite is coconut coir. This is the brown fiber at the palm frond’s base, which has been shredded into small bits. You buy it as a block and soak it overnight. Use it to fill six packs, 4-inch pots, or 1-gallon pots, depending on what you have.

Perlite is Perfect: Another inert soil-less sprouting medium is perlite. This expanded rock dust is like white popcorn, and like coco coir, it will provide good aeration while not over-wetting the seeds.  Either of the above will prevent the dampening off (aka seed rot) common in seeds started in black soil.

I recommend soaking your seed sprouting pots in 1 inch of water. (Photo by Joshua Burman Thayer)


Step 1: Soak your medium overnight and use it to fill your containers to within ½ inch of the top.

Step 2: Mark your batch to indicate which kind of seeds you are seeding and the date of seeding.

Step 3: Plant according to seed instructions. As a rule of thumb (literally) a seed is planted to a depth of twice the seed’s size.

Step 4: Carefully dust the planted seeds with an additional ¼-inch of coco coir. This will protect the seed from light until it sprouts.

Step 5: With a spray bottle, gently mist your seed starts until the surface is wet.

Step 6: Place planted pots into a pan filled 1 inch deep with water. This will allow soil in the new pots to slowly wick up the moisture as needed.

Step 7: Mist the plants 3 times per week.

Step 8: Once seeds have sprouted, begin to mist with kelp meal added into the water in your spray bottle. Use 1 tablespoon kelp meal in a full 750ml spray bottle.

Step 9: After 2 weeks of misting with kelp, transplant starts into the next size up pot, this time using an O.M.R.I. listed soil blend. These brands have the O.M.R.I. listing: Fox Farm, Happy Frog, Kellogg’s, Roots Organic, and Royal Gold.

Step 10: In April and May, your starts will be large and ready to plant direct into your raised beds.


Beans and celery cohabitate in one sprouting pot. (Photo by Joshua Burman Thayer)

Let Companion Plants Cohabitate!

Try a companion plant co-habitation pot.
Use a 1-gallon pot and try one or more of these combos:

Borage and tomato

Basil and tomato

Cucumber and beans

Peas and squash

Corn and beans

Beans and celery


More about starting summer crops.



While you wait for your seedlings to mature in their pots until summer planting time, consider some fast-growing spring crops. Also known as catch crops, these plants will sprout despite the cool late-winter soil temperatures and will finish in the next 60 days. Simply grow them until they are mature or until you need the real estate for your summer starts.

Arugula: If you can see bare soil in your garden, consider planting arugula in those spots right now. It’s a rewarding and accommodating addition to your cool-season beds. Read more about arugula here.

French Breakfast Radish: Far less spicy than the round varieties, this fertile radish will sprout up from each and every seed you plant. Go slowly and plant them 2-4 inches apart. I put radish in my ramen as a potato replacement.

Garden Peas: Nothing draws kids to the garden like the chance to snack on spring peas, and cultivating this fast-growing plant maximizes the value of your time in the garden. What’s more, peas fix nitrogen and enrich your soil for your summer crops to follow.

More catch crop ideas here.


May the year 2021 be our best growing season yet! Happy gardening.

WANT TO LEARN MORE? Visit Joshua Burman Thayer at nativesungarden.com