Pot Them, Don't Plant Them

We once called it gardening by mail. You received a catalog from, let’s say, Wayside Gardens (no longer on my recommended list) and thumbed through the pages, mulled over your choices for a few days then filled in the order blank, sent it back to the vendor and waited for the delivery. Your plants arrived weeks or months later via mail and in some cases by UPS.

These days it’s all done on the web, but the plants still get shipped through the USPS, UPS and in some cases via FedEx. What you receive, though, can be in several forms. They can be rooted plants in plastic cells, bare roots with a crown packed in damp newspaper, excelsior or peat moss. But what you do with these plants on arrival will have a direct effect on their survival and ability to thrive. Here are some tips and insights into what I do when it’s unboxing time.

First of all, if you’re still ordering plants and have the option, try to get a Monday shipping date. Plants shipped later in the week often can spend days or a long hot weekend in a truck at a distribution center anywhere along the shipping route. Monday shipping is critical for long-distance shipping, and if you’re buying from a nursery on the West Coast, three-day shipping, while expensive, is the best bet. More on this shortly.

The very first thing to do when your box arrives is to open it. Trees, such as bare-rooted fruit trees, will arrive in long rectangular boxes while potted perennials may arrive in smaller boxes appropriate to the quantity you’ve ordered and the size. No matter though. When the box arrives, open it, and don’t let it sit on the front porch in direct sunlight while you dilly dally. Open the box.

In most cases the plants will come with instructions on how to handle them once unpacked. Some nurseries have this down pat, and you won’t see more than a half a cup of soil that’s come loose. Others don’t do such a good job, but you’ll quickly learn which nurseries do it right and which don’t.

Once the plants are unboxed and inspected, check all the plants in cells and pots to see if they need water. Water them as necessary and find a spot where you can put the pots on the ground or porch where they’ll get good light but not direct sunlight. Give them a couple of days before they get hit by the sun. The directions that come with bare-rooted trees will often advise you to rehydrate the root in a bucket of water. This should be done with room temperature tap water, not cold, not hot, but room temp.

No matter what you’ve ordered in the realm of annuals or perennials, if they are bare root or in cells you might consider potting them up instead of directly planting them in beds or containers. Annuals can be potted into 4-inch pots and held that way for two to three weeks to grow on. Planting these seedlings or young plants directly into containers to garden beds will result in substantial losses as you lose control in watering, soil temperature and animal browsers and feeders that may adore the young and tender plants.

I’ve learned to never plant bare-root perennials (and lily bulbs) directly into the garden. Instead I take the extra step of potting these into black plastic nursery containers. This gives you an opportunity to grow the plant for months or years to see if it’s actually true to name and color. It also gives you the opportunity to make better decisions on where the particular plant will do best and look best in your garden and landscape.

Planted directly into these areas without the potting up process results in the plants getting “lost” in the garden and as young tender plants they are more susceptible to browsing by deer and others. Find a holding area on your property where you can line out the pots, maybe fence them in, and make sure there’s a hose bib nearby or the ability to run a hose to that area.

Make a tag or label for each pot so you don’t forget or lose track of what it is. The black plastic nursery pots are widely available at garden centers that often look for ways to recycle them, and I try to keep 50 to 100 of them in storage from year to year. The pots are mostly round and are measured in capacity by quarts and gallons. Most of the time you’ll pot into a 1-quart pot then “bump” the plant up to larger pots as necessary.

You can find or may have square black plastic pots. Nurseries like to use these because they take up less space than the round pots, but they’re only available in 1- and 2-quart sizes. Then you’re up against the age-old problem of planting a square root mass into a round hole. No big deal though.

What you add to the pot in terms of soil is critical. Never, ever use garden soil. It’s usually too heavy and too wet and can contain pathogens we like to keep away from the plants when they’re young. The best general purpose potting mix (NOT potting soil) is ProMix. This is a peat and or peat/bark mix that just about anything will grow in. It comes in bags and bales. Though heavy and expensive, the best value is the compressed bale that should be stored in a garage or shed until it’s used.

I like to mix batches of ProMix in a pail, tray, wheelbarrow or garden cart. It comes out of the bale bone dry and can easily be moistened with warm water. Add small amounts of water as you can always add more but can’t remove excess water easily. The best mix is moist to the touch but not to the point where you can take a fistful and squeeze the water out. If you think you may keep your plants in the pots for several months maybe add a small amount of time-released fertilizer.

Never do this with a white plastic pot or if that’s all you have, sleeve the white plastic pot into a black one. Roots need darkness to thrive. White pots won’t provide this lack of light unless they are black on the inside, and yes, I have seen these.

As an alternative, if you have a well cooked and aged batch of your own compost you can make a mix of half compost and half ProMix. This will give you a soil with more water holding capacity and well as soil microbes that will be missing from your straight peat/bark mix. The key here is that your compost must have cooked and aged so it should probably be a year old.

The fertilizer aspect is critical with these peat and bark based soil mixes — also called soilless mixes. They contain no nutrients for the plants. Nutrients will have to be added as the plants take off. You can add liquid organics or band a small amount of an organic fertilizer to the top of the soil (scratch the right amount into the top half inch of the soil) and repeat every three to four weeks.

Fill the pot (for the first planting smaller is better) to the top and don’t push the soil down or compress it. Using your hand make an appropriate-sized hole or depression for the plant. Bare-rooted plants will need a deeper hole, which can usually be made with your hand used as a wedge pressed into the soil and spreading it. The roots should be allowed to go to the bottom of the wedge hole then backfilled with loose soil.

Don’t press the soil down. Lift the pot and gently drop it on a firm surface and let this action gently “pack” the soil. Whether you’re planting a plant extracted from a cell or a bare rooted plant, the crown should never, ever be below the soil. Moisten the soil with a gentle spray or watering can, but again, don’t over water. Put the potted plant in a dark spot with no sun for a few days, then you can relocate based on the plant’s light needs.

The biggest plus to all the extra steps is that the plant will grow quickly in the black pot as the color will absorb the heat of the sun, stimulating root growth. Later on the pots will need shading from the sun with a board or other pots since once we get into mid to late May the sun will overheat the pots. The pots can also be sunk into the ground for long term storage and growing on, without the need for more repotting.

Later in the summer, any or all of these plants can be planted directly into the garden with little to no planting shock. Simply dig the appropriate hole size in the garden (same size as the pot or slightly larger) to receive the de-potted plant and backfill with garden soil or compost.

That’s it in a nutshell, or better put, in a black plastic pot. It’s extra work but certainly pays off in having better plants to plant. And since these come out of pots, the replanting can be done any time in the planting season up to early September. This gives the de-potted and newly planted specimens time to further establish roots into the garden soil and get ready for winter.

Next week, growing just about anything from seed and how. As well as what you can’t grow from seed. Keep growing.

GARDEN NOTES

The Hampton Gardener’s favorites for plants by mail:

Bluestone Perennials ships their perennials mostly in cells and their varieties don’t include many new introductions. They also sell some trees and shrubs.

For the gardener with some experience there’s Plant Delights Nursery. A wide range of perennials, annuals (tender perennials) and plants to experiment with.

Edelweiss Perennials is in Oregon but has the largest listing of perennials you’ll ever find. They ship bare root mostly via three-day USPS.

Burpee and others now seem to be catalogs only with their plants shipped from other growers as “drop shipped.” I always prefer going right to the source.