Q: I know that it is time to prune other bushes, but should I prune my roses also?
A: I would wait. Pruning tells all plants that it is time to get busy and start some new growth. For many bushes that would not be a problem. But new shoots on roses are very tender. Hard freezes would kill the buds that the pruning had encouraged; the cold might kill buds even before they were visible. Unless it is a strange spring, we still will have some freezes on clear nights.
Rather than try to learn a calendar date for pruning roses, I prune mine when the daffodils bloom. Although an occasional spring will produce a very cold night later than that, it is rare. Daffodil flowers and roses pruning seem to be a safe match.
Q: I am going to plant an asparagus bed. How soon can I plant? How do I do it? How many years will it be before we can eat some asparagus?
A: Plant as soon as possible. The longer the crowns have in the ground, the more roots they will grow this summer. Asparagus is a long-term investment. Locate the bed where it will get lots of sun, and where the soil is rich. If in doubt about the soil, top it up with an inch of compost and plan to add more compost or manure annually. Asparagus plants are always hungry.
Perhaps the most important preparation is to create an 18 inch strip around the bed, where weeds will never live. Grasses are particularly adept at moving into an asparagus bed; once established, they are very difficult to remove. You may want to till a surrounding path, or you may want to cover the strip with some opaque material.
Allow at least two feet between asparagus crowns when you plant them. They may be small now but will grow rapidly. Some gardeners plant at the bottom of a trench and fill it gradually. I plant crowns four inches deep, because asparagus has contractile roots that will pull themselves down if they want to be deeper. Keep the bed weeded (and watered, of course) all summer.
Rather than beginning harvest on a time schedule, let the asparagus tell you when it has grown enough to cut some stalks. Cut only stalks which are at least as thick as a lead pencil. In their second year, asparagus plants will make a few stalks that size, with numbers increasing annually as the crowns grow bigger.
Asparagus is an early vegetable. As summer progresses, the crowns use up their stored energy and begin to produce thinner stalks. That is a sign that the end of the year's harvest is coming. No matter how fat the remaining stalks are, stop all cutting by the Fourth of July. That will give the plants the rest of the summer to grow their ferny leaves. The ferns in turn will build the underground buds which become the next year's crop.
If you start from seed, as I did, allow an extra year before the first harvest. Grow asparagus seedlings a few inches apart for their first summer. The following spring, transplant the young asparagus crowns to a permanent bed.
Weeding an asparagus bed is the most crucial part of growing asparagus. The plants are not fighters. They can be bullied into scant production by any strong weed which wants to make its home in the asparagus bed. Nor do asparagus plants, with their delicate foliage, ever shade weeds out of existence. If you have time for only one bit of weeding, take your tools to the asparagus bed first.
Q: Should I repot into bigger containers the tomatoes I started from seed, before I move the plants to the garden?
A: Probably, but it depends on the size pots you start tomato plants in, and how long they grow in pots. The process always is a delicate balance between various possibilities. Some gardeners start many plants in a flat to save space, then cut the soil into blocks and transplant the healthiest starts to individual pots. I choose to start tomatoes in two-inch pots, three seeds in each, then cut off the two weakest seedlings in every pot.
I grow my tomatoes about six weeks before moving the plants to the garden. When roots fill the little pots, I transplant to pots that are five inches deep. It would be possible to set out younger tomato plants and never have to transplant them. Plants grown longer indoors might need to move to larger pots twice on their way to the final destination.
The disadvantage of transplanting is that every time it happens, seedlings lose about a week of growing time while they recover from the stress of the move. The advantage of transplanting is that roots are never cramped or distorted by a shortage of dirt for spreading out.
One lesson I learned the hard way: after moving seedlings from small to larger pots, wait at least two weeks before planting in the garden. That much time is necessary for roots to branch out into new potting soil and hold everything together. If plants are turned out of a pot too soon, no matter how carefully, most of the soil will fall off the root ball, taking pieces of root along in the free fall.
This is the time when all the spring bulbs are appearing — the little early ones in bloom, the later ones at least showing their first furled leaves. They announce the beginning glory of the garden season. Writer Anna Pavord says, "The best thing about bulbs is that so often you forget you have planted them. Then, suddenly in spring, there they are, not the slightest bit put out that you have not been worrying over them or making them special snacks."
There is an enormous bulb garden in the Netherlands called Hortus Bulborum, which safeguards 2700 varieties of tulips by growing them every year. The garden is run entirely by volunteers, most of them retired from the commercial bulb business. It is open to the public for two weeks during the flowering season, and some extra bulbs are sold to pay expenses.
Some of the tulip varieties are heirlooms available nowhere else in the world. They even include the striped tulips famously portrayed in Rembrandt's paintings. These are the bulbs that caused Tulipmania from 1635 to 1637. Fortunes were made and destroyed in that bubble. Today those tulips are grown nowhere else because the stripes are caused by a virus infection. No gardener wants the virus loose among their plants. Fields are inspected regularly, and any other flower possibly infected by the virus is killed with herbicide. Thus does the Dutch bulb business protect itself from disaster, while keeping alive rare and famous flowers.